Method of determining frequency-domain offset parameter, user equipment (UE), random access method, method for configuring random access information, corresponding device and computer readable medium

ABSTRACT

The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). A method of determining a frequency-domain offset parameter of a preamble in a random access channel and a corresponding user equipment (UE) is provided. The method includes obtaining a random access channel subcarrier spacing Δf RA , a preamble length L RA  and a uplink (UL) channel subcarrier spacing Δf from a base station and determining a frequency-domain offset parameter  k  of a preamble in a random access channel based on the obtained random access channel subcarrier spacing Δf RA , preamble length L RA  and UL channel subcarrier spacing Δf. Other embodiments of the disclosure further provide a random access method, a method for configuring random access information and related device, and a corresponding computer readable medium.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is based on and claims priority under 35 U.S.C. §119(a) of a Chinese patent application number 201810027186.8, filed onJan. 11, 2018, in the Chinese Patent Office, and of a Chinese patentapplication number 201810057947.4, filed on Jan. 19, 2018, in theChinese Patent Office, the disclosure of each of which is incorporatedby reference herein in its entirety.

BACKGROUND 1. Field

The disclosure relates to wireless communication technology. Moreparticularly, the disclosure relates to a method of determining afrequency-domain offset parameter, a user equipment (UE), a randomaccess method, a method for configuring random access information, acorresponding device and a computer readable medium related thereto.

2. Description of Related Art

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a ‘Beyond 4G Network’ or a‘Post LTE System’. The 5G communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, soas to accomplish higher data rates. To decrease propagation loss of theradio waves and increase the transmission distance, the beamforming,massive multiple-input multiple-output (MIMO), Full Dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, large scale antennatechniques are discussed in 5G communication systems. In addition, in 5Gcommunication systems, development for system network improvement isunder way based on advanced small cells, cloud Radio Access Networks(RANs), ultra-dense networks, device-to-device (D2D) communication,wireless backhaul, moving network, cooperative communication,Coordinated Multi-Points (CoMP), reception-end interference cancellationand the like. In the 5G system, Hybrid FSK and QAM Modulation (FQAM) andsliding window superposition coding (SWSC) as an advanced codingmodulation (ACM), and filter bank multi carrier (FBMC), non-orthogonalmultiple access (NOMA), and sparse code multiple access (SCMA) as anadvanced access technology have been developed.

The Internet, which is a human centered connectivity network wherehumans generate and consume information, is now evolving to the Internetof Things (IoT) where distributed entities, such as things, exchange andprocess information without human intervention. The Internet ofEverything (IoE), which is a combination of the IoT technology and theBig Data processing technology through connection with a cloud server,has emerged. As technology elements, such as “sensing technology”,“wired/wireless communication and network infrastructure”, “serviceinterface technology”, and “Security technology” have been demanded forIoT implementation, a sensor network, a Machine-to-Machine (M2M)communication, Machine Type Communication (MTC), and so forth have beenrecently researched. Such an IoT environment may provide intelligentInternet technology services that create a new value to human life bycollecting and analyzing data generated among connected things. IoT maybe applied to a variety of fields including smart home, smart building,smart city, smart car or connected cars, smart grid, health care, smartappliances and advanced medical services through convergence andcombination between existing Information Technology (IT) and variousindustrial applications.

In line with this, various attempts have been made to apply 5Gcommunication systems to IoT networks. For example, technologies such asa sensor network, Machine Type Communication (MTC), andMachine-to-Machine (M2M) communication may be implemented bybeamforming, MIMO, and array antennas. Application of a cloud RadioAccess Network (RAN) as the above-described Big Data processingtechnology may also be considered to be as an example of convergencebetween the 5G technology and the IoT technology.

With the rapid development of the information industry, especially agrowing demand from mobile Internet and Internet of things (IoT),unprecedented challenges have been brought to the future mobilecommunication technology. For example, according to the report ITU-R M.[IMT.BEYOND 2020.TRAFFIC] of the international telecommunication union(ITU), it may be expected that by 2020, the amount of mobile trafficwill increase by nearly 1,000 times relative to that in 2010 (fourthgeneration (4G) era), and the number of connected UEs will exceed 17billion. As massive IoT devices gradually penetrate into the mobilecommunication network, the number of connected devices will be even moreremarkable. In response to the unprecedented challenge, thecommunications industry and academia have developed extensive 5^(th)generation (5G) mobile communications technology researches for the2020's. In the current ITU report ITU-R M. [IMT.VISION], the future 5Gframework and overall objectives have already been discussed, in whichthe 5G demand outlook, application scenarios, and various importantperformance indicators are described in detail. For new requirements in5G, the ITU report ITU-R M. [IMT.FUTURE TECHNOLOGY TRENDS] providesinformation related to 5G technology trends, aiming to addresssignificant issues associated with increase in system throughput, userexperience consistency, scalability for IoT support, latency, energyefficiency, cost, network flexibility, support for emerging services,and flexible spectrum utilization etc.

A random access process is important means for user equipment (UE)access. After the UE has completed downlink (DL) synchronization basedon a DL synchronization signal, it needs to enter the random accessprocess, in order to complete registration in a cell and obtain anuplink (UL) timing advance instruction to complete UL synchronization.The random access may be classified as contention-based random accessand contention-free random access based on whether or not the UEassociated with preamble resources exclusively. Since in thecontention-based random access, respective UEs select respectivepreambles from the same preamble resources in a process of trying toestablish UL links, several UEs may select the same preamble to betransmitted to the base station. Thus, a conflict resolution mechanismis an important research direction in the random access. How to reduce aconflict probability and how to rapidly resolve a conflict which hasoccurred are key indicators that affect the random access performance.

FIG. 1 illustrates a schematic diagram of a contention-based randomaccess process according to the related art.

Referring to FIG. 1, the contention-based random access process in longterm evolution-advanced (LTE-A) includes four operations. Before therandom access process starts, the base station transmits configurationinformation of the random access process to the UE, and the UE performsthe random access process according to the received configurationinformation.

In operation 1, the UE randomly selects a preamble from a preambleresource pool and transmits it to the base station and the base stationperforms correlation detection on the received signal so as to identifythe preamble transmitted by the UE.

In operation 2, the base station transmits a random access response(RAR) to the UE, the RAR including a random access preamble identifier,a timing advance instruction determined based on a delay estimationbetween the UE and the base station, a temporary cell-radio networktemporary identifier (TC-RNTI), and time-frequency resources allocatedfor the next UL transmission of the UE.

In operation 3, the UE transmits a Message 3 (MSg3) to the base stationaccording to the information in the RAR. The MSg3 includes information,such as a UE identifier for identifying a UE and a radio resourcecontrol (RRC) link request, etc. The UE identifier is an identifierunique to the UE for resolving conflicts.

In operation 4, the base station transmits a conflict resolutionidentifier to the UE, including the UE identifier of the UE thatsurvives the conflict resolution. After detecting its own identifier,the UE upgrades a TC-RNTI to a cell-radio network temporary identifier(C-RNTI), and transmits an acknowledgement (ACK) signal to the basestation to complete the random access process, and then waits forscheduling by the base station, otherwise, the UE will start a newrandom access process after a delay.

For the contention-free random access process, since the base stationknows the UE identifier, it may allocate a preamble for the UE.Therefore, when the UE intends to transmit a preamble, it does not needto randomly select a preamble, but may use the allocated preamble. Afterdetecting the allocated preamble, the base station may transmit acorresponding RAR, including information, such as timing advance and ULresource allocation etc. After receiving the RAR, the UE considers thatUL synchronization has been completed and waits for further schedulingby the base station. Therefore, the process of initial access and thecontention-free random access only include two operations Firstoperation of transmitting a preamble and Second operation oftransmitting an RAR.

In either a contention-based or contention-free random access, the firstoperations in initiating the random access is to transmit a preamble onthe random access channel. In LTE, an equation for generating a basebandsignal is given as

${s(t)} = {\beta_{PRACH}{\sum\limits_{k = 0}^{N_{ZC} - 1}{\sum\limits_{n = 0}^{N_{ZC} - 1}{{x_{u,v}(n)} \cdot e^{{- j}\frac{2\pi\;{nk}}{N_{ZC}}} \cdot e^{j\; 2{\pi{({k + \varphi + {K{({k_{0} + \frac{1}{2}})}}})}}\Delta\;{f_{RA}{({t - T_{CP}})}}}}}}}$

In the above equation, β_(PRACH) is an amplitude adjustment factorcalculated in a power control process, N_(ZC) is a preamble length,x_(u,v)(n) is a preamble, K is a factor for adjusting a differencebetween a random access channel subcarrier spacing and a UL channelsubcarrier spacing, Δf_(RA) is a random access channel subcarrierspacing, k₀ is a parameter for adjusting a frequency-domain position ofa random access channel, T_(CP) is a cyclic prefix length, and aparameter φ is used to adjust a frequency-domain position of a randomaccess preamble, so that its distances from two ends of a bandwidth of aUL shared channel are identical (i.e., guard periods on both sides ofthe preamble are identical), with its specific values shown in Table 1.

TABLE 1 Values of Parameter φ Preamble Format Δf_(RA) φ 0-3 1250 Hz 7 47500 Hz 2

It can be seen that the parameter φ is directly associated with a randomaccess channel subcarrier spacing.

For a 5G system, the subcarrier spacing supported by the system and thesubcarrier spacing supported by the random access channel are morediversified. Specifically, the UL-supported subcarrier spacing includes15/30/60/120 kHz, while the random access channel subcarrier spacingincludes 1.25/5/15/30/60/120 kHz. Various combinations of the UL channelsubcarrier spacing and the random access channel subcarrier spacing makeadjustment of the preamble position more complex.

In the existing 5G technologies, the UL-supported subcarrier spacing andthe subcarrier spacing supported by the random access channel are morediversified. A single or a few parameters used to adjust thefrequency-domain position of the preamble cannot satisfy all possiblecombinations of the subcarrier spacing.

In addition, when there is a supplementary uplink in the system, thetransmission flow of the existing random access preamble may besummarized as follows

The terminal receives the random access configuration informationcarried by the master information block (MIB) carried in the broadcastchannel or by the remaining minimum system information (RMSI) indicatedin the MIB, as well as the threshold information for selecting theuplink. Subsequently, the terminal determines whether to select thesupplementary uplink according to the reference signal received power(RSRP) of the downlink of the 5G system, that is, if the RSRP is lessthan the threshold information, then the supplementary uplink isselected to transmit the random access preamble, otherwise, the uplinkof the 5G system is selected to transmit the random access preamble.Subsequently, the terminal determines the time-frequency resources ofthe random access channel according to the random access channelconfiguration information, and selects the preamble according to therandom access preamble configuration information. Finally, the terminaltransmits the preamble.

However, in the existing 5G technology, if the system selects the uplinkof the 5G system according to the RSRP, or selects the supplementaryuplink to transmit the random access preamble, then the subsequentrandom access reattempt will further be performed on the selecteduplink, which will most likely cause the subsequent random accessprocedure to continue to fail due to the quality problem of the uplinkchannel, affecting the system performance, and further affecting theaccess experience of the terminal.

The above information is presented as background information only toassist with an understanding of the disclosure. No determination hasbeen made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the disclosure.

SUMMARY

The technical problem intended to be solved by the disclosure is that inthe scheme of the related art, the parameters for adjusting thefrequency-domain position of the preamble cannot satisfy variouspossible combinations of uplink (UL) shared channel subcarrier spacingand random access channel subcarrier spacing in 5^(th) generation (5G).

Aspects of the disclosure are to address at least the above-mentionedproblems and/or disadvantages and to provide at least the advantagesdescribed below. Accordingly, an aspect of the disclosure is to providea scheme of determining a frequency-domain offset parameter of apreamble in a random access channel, which are applicable to variouscombinations of subcarrier spacing.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

In accordance with an aspect of the disclosure, a method of determininga frequency-domain offset parameter of a preamble in a random accesschannel is provided. The method includes obtaining a random accesschannel subcarrier spacing Δf_(RA), a preamble length L_(RA) and a ULchannel subcarrier spacing Δf from a base station and determining afrequency-domain offset parameter k of a preamble in a random accesschannel based on the obtained random access channel subcarrier spacingΔf_(RA), preamble length L_(RA) and UL channel subcarrier spacing Δf.

In accordance with another aspect of the disclosure, a user equipment(UE) is provided. The UE includes a processor and a memory storingcomputer-executable instructions which, when executed by the processor,cause the processor to obtain a random access channel subcarrier spacingΔf_(RA), a preamble length L_(RA) and a UL channel subcarrier spacing Δffrom a base station and determine a frequency-domain offset parameter kof a preamble in a random access channel based on the obtained randomaccess channel subcarrier spacing Δf_(RA), preamble length L_(RA) and ULchannel subcarrier spacing Δf.

In an embodiment of the disclosure, the operation of determining thefrequency-domain offset parameter k of the preamble in the random accesschannel further includes calculating the frequency-domain offsetparameteric of the preamble in the random access channel according to anequation given as

${\overset{\_}{k} = \left\lbrack {\frac{N_{u} + 1}{2} - {\frac{1}{2}\frac{\Delta\; f}{\Delta\; f_{RA}}}} \right\rbrack},$wherein N_(u) represents a number of subcarriers in the random accesschannel that are used as a guard band, and a symbol [⋅] represents arounding operation.

In an embodiment of the disclosure, the operation of determining thefrequency-domain offset parameter k of the preamble in the random accesschannel further includes calculating the frequency-domain offsetparameter k of the preamble in the random access channel according to anequation given as

${\overset{\_}{k} = \left\lbrack {\frac{N_{u}}{2} - {\frac{1}{2}\frac{\Delta\; f}{\Delta\; f_{RA}}}} \right\rbrack},$Wherein N_(u) represents a number of subcarriers in the random accesschannel that are used as a guard band, and a symbol [⋅] represents arounding operation.

In an embodiment of the disclosure, the operation of determining thefrequency-domain offset parameter k of the preamble in the random accesschannel further includes calculating the frequency-domain offsetparameter k of the preamble in the random access channel according to anequation given as k=[N_(u)/2], wherein N_(u) represents a number ofsubcarriers in the random access channel that are used as a guard band,and a symbol [⋅] represents a rounding operation.

In an embodiment of the disclosure,

$N_{u} = \frac{\left( {{N_{SC}N_{RB}^{RA}\Delta\; f} - {L_{RA}\Delta\; f_{RA}}} \right)}{\Delta\; f}$wherein N_(RB) ^(RA) is a number of random access channel physicalresource blocks

$N_{RB}^{RA} = \left\lceil \frac{L_{RA}\Delta\; f_{RA}}{\Delta\;{fN}_{SC}} \right\rceil$per UL channel subcarrier spacing Δf, a symbol ┌⋅┐ is a ceilingoperation, and N_(SC) is a number of subcarriers in one physicalresource block.

In an embodiment of the disclosure, N_(u) is obtained according to acorrespondence table given as

NUMBER OF RANDOM ACCESS CHANNEL PHYSICAL RESOURCE BLOCKS (PER UL CHANNELL_(RA) Δf_(RA) Δf SUBCARRIER SPACING) N_(u) 839 1.25 15 6 25 839 1.25 303 25 839 1.25 60 2 313 839 5 15 24 25 839 5 30 12 25 839 5 60 6 25 13915 15 12 5 139 15 30 6 5 139 15 60 3 5 139 30 15 24 5 139 30 30 12 5 13930 60 6 5 139 60 60 12 5 139 60 120 6 5 139 120 60 24 5 139 120 120 12 5

In an embodiment of the disclosure, the operation of determining thefrequency-domain offset parameter k of the preamble in the random accesschannel further includes determining the frequency-domain offsetparameter k of the preamble in the random access channel according toone of correspondence tables given as

NUMBER OF RANDOM ACCESS CHANNEL PHYSICAL RESOURCE BLOCKS (PER UL CHANNELL_(RA) Δf_(RA) Δf SUBCARRIER SPACING) k 839 1.25 15 6 7 839 1.25 30 3 1839 1.25 60 2 133  839 5 15 24 12  839 5 30 12 10  839 5 60 6 7 139 1515 12 3 139 15 30 6 2 139 15 60 3 1 139 30 15 24 3 139 30 30 12 3 139 3060 6 2 139 60 60 12 3 139 60 120 6 2 139 120 60 24 3 139 120 120 12  3;

NUMBER OF RANDOM ACCESS CHANNEL PHYSICAL RESOURCE BLOCKS (PER UL CHANNELL_(RA) Δf_(RA) Δf SUBCARRIER SPACING) k 839 1.25 15 6 7 839 1.25 30 3 1839 1.25 60 2 133  839 5 15 24 11  839 5 30 12 10  839 5 60 6 7 139 1515 12 2 139 15 30 6 2 139 15 60 3 1 139 30 15 24 2 139 30 30 12 2 139 3060 6 2 139 60 60 12 2 139 60 120 6 2 139 120 60 24 2 139 120 120 12  2;or

NUMBER OF RANDOM ACCESS CHANNEL PHYSICAL RESOURCE BLOCKS (PER UL CHANNELL_(RA) Δf_(RA) Δf SUBCARRIER SPACING) k 839 1.25 15 6 13  839 1.25 30 313  839 1.25 60 2 157  839 5 15 24 13  839 5 30 12 13  839 5 60 6 13 139 15 15 12 3 139 15 30 6 3 139 15 60 3 3 139 30 15 24 3 139 30 30 12 3139 30 60 6 3 139 60 60 12 3 139 60 120 6 3 139 120 60 24 3 139 120 12012  3.

In accordance with another aspect of the disclosure, a random accessmethod is provided. The random access method includes performing aswitching of an uplink if an uplink switching condition is satisfiedwhen a random access is performed based on a determined uplink and therandom access fails and performing a random access based on theafter-switching uplink.

In accordance with another aspect of the disclosure, a method forconfiguring random access information is provided. The method includesdetermining relevant configuration information for performing randomaccess on at least two uplinks respectively, the configurationinformation comprises information for performing a switching between atleast two uplinks, and transmitting the configuration information.

In accordance with another aspect of the disclosure, a terminal deviceis provided. The terminal device includes a switching device configuredto perform a switching of an uplink if an uplink switching condition ismet, when a random access is performed based on the determined uplinkand the random access fails and an access device configured to perform arandom access based on the after-switching uplink.

In accordance with another aspect of the disclosure, a base station isprovided. The base station includes a determination device configured todetermine relevant configuration information for performing randomaccess on at least two uplinks, wherein the configuration informationincludes information for performing a switching between at least twouplinks and a transmission device configured to transmit theconfiguration information.

In accordance with another aspect of the disclosure, a terminal deviceis provided. The terminal device includes a processor and a memoryconfigured to store machine-readable instructions that, when executed bythe processor, cause the processor to perform the random access methoddescribed above.

In accordance with another aspect of the disclosure, a base station isprovided. The base station includes a processor and a memory configuredto store machine-readable instructions that, when executed by theprocessor, cause the processor to perform the above-described method forconfiguring random access information.

In accordance with another aspect of the disclosure, a computer-readablemedium is provided. The computer-readable medium has stored thereoninstructions which, when executed by a processor, cause the processor toperform the method as described above.

An embodiment of the disclosure provides a random access method. When arandom access is performed based on the determined uplink and the randomaccess fails, if the uplink switching condition is met, a switching isperformed on the link, so that when the random access procedure attemptfails, whether the uplink switching condition is satisfied is determinedin time, so as to determine whether a switching may be performed to theuplink with better channel condition so as to perform a random access.Moreover, the transmission is switched to the link when the uplinkswitching condition is met, which provides a precondition for asubsequent random access based on the after-switching link, and a randomaccess is performed based on the after-switching uplink. When the randomaccess attempt fails, the terminal may timely select the uplink withbetter channel quality to reattempt the random access procedure andperform a random access based on the after-switching uplink, thusreducing the delay of the random access and improving the overallperformance of the system.

An embodiment of the disclosure provides a method for configuring randomaccess information, which determines relevant configuration informationused for performing random access on at least two uplinks respectively,wherein the configuration information includes information used forperforming a switching between at least two uplinks, thus providing apremise guarantee for the terminal to perform random access on multipleuplinks and a switching between multiple uplinks. The configurationinformation is transmitted so that the terminal can perform acorresponding random access on multiple uplinks according to theconfiguration information when performing the random access.

In accordance with an aspect of the disclosure, a method by terminal isprovided. The method includes receiving, from a base station, firstinformation related to a length of a random access preamble and a firstsubcarrier spacing of a random access channel, receiving, from the basestation, second information related to a second subcarrier spacing of aphysical uplink shared channel (PUSCH), identifying an offset parameterbased on the length of the random access preamble, the first subcarrierspacing, and the second subcarrier spacing, the offset parameter beingused to identify a frequency resource of the random access channel, andtransmitting the random access preamble based on the offset parameter.

In accordance with an aspect of the disclosure, a method by base stationis provided. The method includes transmitting, to a terminal, firstinformation related to a length of a random access preamble and a firstsubcarrier spacing of a random access channel, transmitting, to theterminal, second information related to a second subcarrier spacing of aphysical uplink shared channel (PUSCH), and receiving the random accesspreamble based on an offset parameter which is identified based on thelength of the random access preamble, the first subcarrier spacing, andthe second subcarrier spacing, wherein the offset parameter is used toidentify a frequency resource of the random access channel.

In accordance with an aspect of the disclosure, a terminal is provided.The terminal includes a transceiver; and at least one processorconfigured to receive, from a base station, first information related toa length of a random access preamble and a first subcarrier spacing of arandom access channel, receive, from the base station, secondinformation related to a second subcarrier spacing of a physical uplinkshared channel (PUSCH), identify an offset parameter based on the lengthof the random access preamble, the first subcarrier spacing, and thesecond subcarrier spacing, the offset parameter being used to identify afrequency resource of the random access channel, and transmit the randomaccess preamble based on the offset parameter.

In accordance with an aspect of the disclosure, a base station isprovided. The base station includes a transceiver, and at least oneprocessor configured to determine a resource of a random access channel,transmit, to a terminal, first information related to a length of arandom access preamble and a first subcarrier spacing of a random accesschannel, transmit, to the terminal, second information related to asecond subcarrier spacing of a physical uplink shared channel (PUSCH),and receive the random access preamble based on an offset parameterwhich is identified based on the length of the random access preamble,the first subcarrier spacing, and the second subcarrier spacing, whereinthe offset parameter is used to identify a frequency resource of therandom access channel.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses various embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 illustrates a schematic diagram of a contention-based randomaccess process according to the related art;

FIG. 2 illustrates a flowchart of a method performed at a user equipment(UE) for determining a frequency-domain offset parameter of a preamblein a random access channel according to an embodiment of the disclosure;

FIG. 3 illustrates a schematic diagram of a random access channel guardband according to an embodiment of the disclosure;

FIG. 4 illustrates schematic diagram of a random access channel guardband according to an embodiment of the disclosure;

FIG. 5 illustrates a structural schematic diagram of a UE according toan embodiment of the disclosure;

FIG. 6 illustrates a discrete fourier transform (DFT)-based basebandsignal generation method according to an embodiment of the disclosure;

FIG. 7 illustrates an improved preamble baseband signal generationmethod according to an embodiment of the disclosure;

FIG. 8 illustrates method of generating a baseband signal according toan embodiment of the disclosure;

FIG. 9 illustrates a schematic flowchart of a random access methodaccording to an embodiment of the disclosure;

FIG. 10 illustrates a schematic flowchart of a random access methodaccording to an embodiment of the disclosure;

FIG. 11 illustrates a schematic diagram of a basic process of a randomaccess method according to an embodiment of the disclosure;

FIG. 12 illustrates a schematic diagram of a basic structure of aterminal device according to an embodiment of the disclosure;

FIG. 13 illustrates a basic structural diagram of a base stationaccording to an embodiment of the disclosure; and

FIG. 14 illustrates a block diagram of a computing system that may beused to implement a base station or UE according to an embodiment of thedisclosure.

Throughout the drawings, it should be noted that like reference numbersare used to depict the same or similar elements, features, andstructures.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thedisclosure. In addition, descriptions of well-known functions andconstructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of thedisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of thedisclosure is provided for illustration purpose only and not for thepurpose of limiting the disclosure as defined by the appended claims andtheir equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

It should be further understood that the word “comprising” used in thedescription of the disclosure refers to presence of features, integers,operations, elements, and/or components, but does not exclude presenceor addition of one or more other features, integers, operations,elements, components, and/or combinations thereof. It should beunderstood that when an element is referred to as being “connected” or“coupled” to another element, it can be directly connected or coupled tothe other element, or there may also be intermediate elements. Inaddition, “connected” or “coupled” as used herein may include wirelesslyconnected or wirelessly coupled. As used herein, the phrase “and/or”includes all or any of one or more of associated listed items, and allof combinations thereof.

It may be understood by the skilled in the art that, unless otherwisedefined, all terms (including technical and scientific terms) usedherein have the same meaning as commonly understood by the skilled inthe art to which the disclosure belongs. It should also be understoodthat the terms, such as those defined in a general dictionary should beunderstood as having a meaning that is consistent with that in thecontext of the prior art, and will not be explained with an idealized ortoo formal meaning, unless specifically defined herein.

The skilled in the art may understand that the “user equipment (UE)”,“terminal” and “terminal device” used herein include not only a wirelesssignal receiver device, which is a device only having a wireless signalreceiver without a transmitting capability, but also a device withreceiving and transmitting hardware, which is a device having receivingand transmitting hardware capable of performing a bidirectionalcommunication over a bidirectional communication link. Such a device mayinclude: a cellular or other communication device having a single linedisplay or a multi-line display or a cellular or other communicationdevice without a multi-line display; a personal communication service(PCS), which may combine voice, data processing, fax and/or datacommunication capabilities; a personal digital assistant (PDA), whichmay include a radio frequency (RF) receiver, a pager, Internet/Intranetaccess, a web browser, a notepad, a calendar, and/or a globalpositioning system (GPS) receiver; a laptop and/or palmtop computer orother device of the related art, which may be a laptop and/or palmtopcomputer or other device of the related art having and/or including anRF receiver. The “terminal”, “terminal device” as used herein may beportable, transportable, installed in a vehicle (of aviation, maritime,and/or land), or may be adapted and/or configured to operate locally,and/or may operate in a distributed form on the earth and/or at anyother locations in space. The “UE” and “terminal” used herein may alsobe a communication terminal, an Internet terminal, a music/video playingterminal, such as a PDA, a mobile Internet device (MID), and/or a mobilephone having a music/video playback function, or a smart television(TV), a set-top box and other devices. In addition, “UE” and “terminal”may also be replaced with “user” and “UE”.

For the purpose of addressing the issue with the solution of the relatedart that the parameters for adjusting the frequency-domain position ofthe preamble cannot satisfy various possible combinations of the uplink(UL) shared channel subcarrier spacing and the random access channelsubcarrier spacing in 5^(th) generation (5G), an embodiment of thedisclosure provides a method performed at a UE for generating a basebandsignal. The method includes reading random access configurationinformation from a base station, which includes random access channelconfiguration information and preamble configuration information, etc.,obtaining a random access channel subcarrier spacing from the randomaccess channel configuration information, and obtaining preamble lengthinformation from the preamble configuration information; and obtaining aUL channel subcarrier spacing from other system information, such asremaining minimum system information (RMSI), transmitted from the basestation, determining a frequency-domain offset parameter of the preamblein a random access channel based on the obtained random access channelsubcarrier spacing, UL channel subcarrier spacing, and preamble sequencelength, and generating a baseband signal based on the determinedfrequency-domain offset parameter of the preamble in the random accesschannel.

Specifically, the baseband signal is generated according to Equation 1:

$\begin{matrix}{{{s_{l}^{({p,\mu})}(t)} = {\sum\limits_{k = 0}^{L_{RA} - 1}{a_{k}^{({p,{PA}})} \cdot e^{j\; 2{\pi{({k + {Kk}_{0} + \overset{\_}{k}})}}\Delta\;{f_{RA}{({t - {N_{{CP},l}^{RA}T_{c}}})}}}}}}{K = {\Delta\;{f/\Delta}\; f_{RA}}}} & {{Equation}\mspace{14mu} 1}\end{matrix}$

where a parameter L_(RA) is a preamble length, k₀ is a parameter foradjusting a position of a random access channel, Δf is a UL data channelsubcarrier spacing or a UL channel subcarrier spacing for initialaccess, Δf_(RA) is a random access channel subcarrier spacing, N_(CP,l)^(RA) is a cyclic prefix length of a preamble, T_(c) is a samplinginterval, and k is a parameter for adjusting a position of a preamble ina random access channel, i.e., a frequency-domain offset parameter of apreamble in a random access channel as used herein.

Thus, the disclosure focuses on determination of the frequency-domainoffset parameter k of the preamble in the random access channel.

Hereinafter, a flowchart of a method performed at a UE for determining afrequency-domain offset parameter of a preamble in a random accesschannel according to an embodiment of the disclosure will be describedwith reference to FIG. 2.

FIG. 2 illustrates a flowchart of a method performed at a UE fordetermining a frequency-domain offset parameter of a preamble in arandom access channel according to an embodiment of the disclosure.

Referring to FIG. 2, the method may include operations 201 and 202.

In operation 201, the UE may obtain a random access channel subcarrierspacing Δf_(RA), a preamble length L_(RA) and a UL channel subcarrierspacing Δf from a base station.

In operation 202, the UE may determine a frequency-domain offsetparameter k of a preamble in a random access channel based on theobtained random access channel subcarrier spacing Δf_(RA), preamblelength L_(RA) and UL channel subcarrier spacing Δf.

The frequency domain offset parameter k of the preamble in the randomaccess channel may be obtained by calculation or by looking up apredefined correspondence table between a frequency-domain offsetparameter k of a preamble in a random access channel and a random accesschannel subcarrier spacing Δf_(RA), a preamble length L_(RA), a ULchannel subcarrier spacing Δf.

Here, “UL channel” refers to a UL data channel, such as a physical ULshared channel (PUSCH), unless stated otherwise.

In an embodiment of obtaining the frequency-domain offset parameter k ofthe preamble in the random access channel by calculation, thefrequency-domain offset parameter k of the preamble in the random accesschannel may be calculated according to the random access channelsubcarrier spacing Δf_(RA), the preamble length L_(RA) and the ULchannel subcarrier spacing Δf obtained from the base station. Theembodiment of the disclosure provides several implementations asfollows.

First Implementation

In this implementation, when a value of the frequency-domain offsetparameter k of the preamble in the random access channel is to becalculated, it is necessary to ensure that guard bandwidths between twoends of the preamble and their closest subcarriers for data transmissionare consistent.

FIG. 3 illustrates a schematic diagram of a random access channel guardband according to an embodiment of the disclosure.

Referring to FIG. 3, a first subcarrier of the random access channel isoverlapped with a subcarrier of the UL channel by setting a parameterKk₀. Thus, a spacing between the first subcarrier of the random accesschannel and a last subcarrier of its adjacent UL channel is one ULchannel subcarrier spacing.

It can be seen that when the guard band between the first subcarrier ofthe preamble and its adjacent UL channel is to be calculated, it isrequired to add a subcarrier bandwidth of the UL channel, in addition tothe guard band within the access random channel; while when the guardband between the last subcarrier of the preamble and its adjacent ULchannel is to be calculated, it is required to add one more subcarrierspacing of the access random channel.

Specifically, assuming that the number, denoted as N_(u), ofsub-carriers used as a guard band within the random access channel maybe obtained by calculating the UL channel subcarrier spacing, the randomaccess channel subcarrier spacing Δf_(RA), and the preamble lengthL_(RA). Thus, when the bandwidths between the two ends of the preambleand their closest subcarriers of the UL channel are to be calculated, abandwidth BW_(g) is (N_(u)+1)Δf_(RA)+Δf, where N_(u)+1 takes intoaccount the subcarriers within the random access channel that are usedas the guard band, and the subcarrier spacing between the lastsubcarrier of the random access channel and its adjacent UL channel,which is the subcarrier spacing of the random access channel; Δf is theUL channel subcarrier spacing, which is used for calculating thebandwidth of the guard band when calculating the distance between thefirst subcarrier of the preamble and its adjacent UL subcarrier. krepresents the number of the random access channel subcarriers withinthe guard band between the first subcarrier of the first preamble andthe last subcarrier of its adjacent UL channel. The parameter k may becalculated as follows.

First, a bandwidth of the random access preamble between the subcarriersof the UL channel at two ends of the random access preamble iscalculated as follows:BW_(g)=(N _(u)+1)Δf _(RA) +Δf

Then, a bandwidth of the guard band on one side may be obtained asfollows:BW_(h)=BW_(g)/2

According to the subcarrier width of the UL channel, the number of thesubcarriers within the random access channel on the side as describedpreviously may be obtained as follows:k =[(BW_(h) −Δf)/Δf _(RA)]

wherein the symbol [⋅] represents a rounding operation, and may bereplaced with a ceil symbol or a floor symbol.

As such, the parameter k may be calculated according to an equation asfollows:

$\begin{matrix}{\begin{matrix}{\overset{\_}{k} = \left\lbrack {{\left( {\frac{{\left( {N_{u} + 1} \right)\Delta\; f_{RA}} + {\Delta\; f}}{2} - {\Delta\; f}} \right)/\Delta}\; f_{RA}} \right\rbrack} \\{= \left\lbrack {\frac{N_{u} + 1}{2} - {\frac{1}{2}\frac{\Delta\; f}{\Delta\; f_{RA}}}} \right\rbrack}\end{matrix}\quad} & {{Equation}\mspace{14mu} 2}\end{matrix}$

where the symbol [⋅] represents a rounding operation, and may bereplaced with a ceil symbol or a floor symbol.

Second Implementation

In this implementation, when a subcarrier spacing within the randomaccess channel is to be calculated, a spacing between the lastsubcarrier within the random access channel and its adjacent UL channelis not calculated. That is, when a guard band between the lastsubcarrier of the preamble and its adjacent UL channel subcarrier is tobe calculated, only the number of subcarriers within the random accesschannel is calculated. In this case, the parameter k is calculated asfollows.

First, a bandwidth of the random access preamble between the subcarriersof the UL channel at two ends of the random access preamble iscalculated as follows:BW_(g) =N _(u) Δf _(RA) +Δf

Then, a bandwidth of the guard band on one side may be obtained asfollows:BW_(h)=BW_(g)/2

According to the subcarrier width of the UL channel, the number of thesubcarriers within the random access channel at the side as describedpreviously may be obtained as follows:k =[(BW_(h) −Δf)/Δf _(RA)]

where the symbol [⋅] represents a rounding operation, and may bereplaced with a ceil symbol or a floor symbol.

As such, the parameter k may be calculated by an equation as follows:

$\begin{matrix}{\begin{matrix}{\overset{\_}{k} = \left\lbrack {{\left( {\frac{{N_{u}\Delta\; f_{RA}} + {\Delta\; f}}{2} - {\Delta\; f}} \right)/\Delta}\; f_{RA}} \right\rbrack} \\{= \left\lbrack {\frac{N_{u}}{2} - {\frac{1}{2}\frac{\Delta\; f}{\Delta\; f_{RA}}}} \right\rbrack}\end{matrix}\quad} & {{Equation}\mspace{14mu} 3}\end{matrix}$

where the symbol [⋅] represents a rounding operation, and may bereplaced with a ceil symbol or a floor symbol.

Third Implementation

FIG. 4 illustrates schematic diagram of a random access channel guardband according to an embodiment of the disclosure.

Referring to FIG. 4, in this implementation, only the number of thesubcarriers within the random access channel is considered, so that thenumbers of the subcarriers on two sides of the random access preambleare approximately equal.

In this case, the number k of the subcarriers for the guard band beforethe first subcarrier of the preamble may be calculated as follows:k =[N _(u)/2]  Equation 4

where the symbol [⋅] represents a rounding operation, and may bereplaced with a ceil symbol or a floor symbol.

Although the disclosure provides only the above three implementations asvarious embodiments of calculating the frequency-domain offset parameterk of the preamble in the random access channel, the disclosure is notlimited thereto. Any other suitable methods of calculating thefrequency-domain offset parameter k of the preamble in the random accesschannel based on the random access channel subcarrier spacing Δf_(RA),the preamble length L_(RA) and the UL channel subcarrier spacing Δf alsofall within the scope of the disclosure.

In the above calculation process, N_(u) is the number of subcarriers inthe random access channel for the guard band, which may be obtained bylooking up a predefined correspondence table (Table 2 as shown below)between N_(u) and the random access channel subcarrier spacing Δf_(RA),the preamble length L_(RA), the UL channel subcarrier spacing Δf, or maybe calculated based on the random access channel subcarrier spacingΔf_(RA), the preamble length L_(RA), and the UL channel subcarrierspacing Δf.

TABLE 2 Number of Subcarriers for Guard Band NUMBER OF RANDOM ACCESSCHANNEL PHYSICAL RESOURCE BLOCKS (PER UL CHANNEL L_(RA) Δf_(RA) ΔfSUBCARRIER SPACING) N_(u) 839 1.25 15 6 25 839 1.25 30 3 25 839 1.25 602 313 839 5 15 24 25 839 5 30 12 25 839 5 60 6 25 139 15 15 12 5 139 1530 6 5 139 15 60 3 5 139 30 15 24 5 139 30 30 12 5 139 30 60 6 5 139 6060 12 5 139 60 120 6 5 139 120 60 24 5 139 120 120 12 5

In the embodiment of obtaining N_(u) by calculation, the number ofrandom access channel physical resource blocks per each UL channelsubcarrier spacing is firstly calculated as follows:

$N_{RB}^{RA} = \left\lceil \frac{L_{RA}\Delta\; f_{RA}}{\Delta\;{fN}_{SC}} \right\rceil$

where N_(SC) is a number of subcarriers in one physical resource block,and a value of N_(SC) may be fixed to be 12; N_(RB) ^(RA) is a number ofrandom access channel physical resource blocks per UL channel subcarrierspacing, and a symbol ┌⋅┐ is a ceiling operation.

The number of sub-carriers within the random access channel which areused as the guard band is then calculated as follows:N _(u)=(N _(SC) N _(RB) ^(RA) Δf−L _(RA) Δf _(RA))/Δf

In the embodiment of obtaining the frequency-domain offset parameter kof the preamble in the random access channel by looking up thepredefined correspondence table between the frequency-domain offsetparameter k of the preamble in the random access channel and the randomaccess channel subcarrier spacing Δf_(RA), the preamble length L_(RA),the UL channel subcarrier spacing Δf, the disclosure provides severalpossible correspondence tables as follows.

A possible correspondence table is shown in Table 3.

TABLE 3 Possible Values of Parameter k NUMBER OF RANDOM ACCESS CHANNELPHYSICAL RESOURCE BLOCKS (PER UL CHANNEL L_(RA) Δf_(RA) Δf SUBCARRIERSPACING) k 839 1.25 15 6 7 839 1.25 30 3 1 839 1.25 60 2 133 839 5 15 2412 839 5 30 12 10 839 5 60 6 7 139 15 15 12 3 139 15 30 6 2 139 15 60 31 139 30 15 24 3 139 30 30 12 3 139 30 60 6 2 139 60 60 12 3 139 60 1206 2 139 120 60 24 3 139 120 120 12 3

Another possible correspondence table is shown in Table 4.

TABLE 4 Other Possible Values of Parameter k NUMBER OF RANDOM ACCESSCHANNEL PHYSICAL RESOURCE BLOCKS (PER UL L_(RA) Δf_(RA) Δf CHANNELSUBCARRIER SPACING) k 839 1.25 15 6 7 839 1.25 30 3 1 839 1.25 60 2 133839 5 15 24 11 839 5 30 12 10 839 5 60 6 7 139 15 15 12 2 139 15 30 6 2139 15 60 3 1 139 30 15 24 2 139 30 30 12 2 139 30 60 6 2 139 60 60 12 2139 60 120 6 2 139 120 60 24 2 139 120 120 12 2

Yet another possible correspondence table is shown in Table 5.

TABLE 5 Yet Other Possible Values of Parameter k NUMBER OF RANDOM ACCESSCHANNEL PHYSICAL RESOURCE BLOCKS (PER UL L_(RA) Δf_(RA) Δf CHANNELSUBCARRIER SPACING) k 839 1.25 15 6 13 839 1.25 30 3 13 839 1.25 60 2157 839 5 15 24 13 839 5 30 12 13 839 5 60 6 13 139 15 15 12 3 139 15 306 3 139 15 60 3 3 139 30 15 24 3 139 30 30 12 3 139 30 60 6 3 139 60 6012 3 139 60 120 6 3 139 120 60 24 3 139 120 120 12 3

In the examples as shown in the above Tables 3, 4 and 5, the predefinedcorrespondence tables are known by both the UE and the base station.Respective parameters k may be obtained from the correspondingcorrespondence tables based on the random access channel subcarrierspacing Δf_(RA), the preamble length L_(RA), the UL channel subcarrierspacing Δf obtained from the base station.

Alternatively, Table 5 may be simplified according to the preambleformat or the preamble length. In particular:

k is 3, if the preamble length L_(RA) is 139;

k is 13, if the preamble length L_(RA) is 839 and the UL channelsubcarrier spacing Δf is not 60 kHz; and

k is 157, if the preamble length L_(RA) is 839 and the UL channelsubcarrier spacing Δf is 60 kHz.

In addition, since both the random access channel subcarrier spacing andthe preamble length are directly determined by the preamble format, thefrequency-domain position offset k may be determined according to thepreamble format and the UL channel subcarrier spacing Δf.

Again, Table 5 is taken as an example:

for the preamble format 0, 1 or 2, if the UL channel subcarrier spacingΔf is not 60 kHz, the frequency-domain offset k is 13; and if the ULchannel subcarrier spacing Δf is 60 kHz, the frequency-domain offset kis 157;

for the preamble format 3, the frequency offset is 13; and

for the preamble format A0, A1, A2, A3, B1, B2, B3, C0, C2 or A1/B1, thefrequency-domain offset k is 3. The above description may also bedetermined by looking up the tables.

For other correspondence tables (e.g., Tables 3 and 4), optimization ofthe correspondence tables may also be performed in a similar way. Forexample, the first two columns of indexes in Tables 3, 4 and 5 may bemerged as the preamble format. For example, possible correspondencetables are shown in Tables 6, 7 and 8.

TABLE 6 A Possible Way of Determining Parameter k NUMBER OF RANDOMACCESS CHANNEL PHYSICAL RESOURCE Preamble BLOCKS (PER UL Format ΔfCHANNEL SUBCARRIER SPACING) k 0, 1, 2 15 6 7 30 3 1 60 2 133 3 15 24 1230 12 10 60 6 7 A0, A1, 15 12 3 A2, A3, 30 6 2 B1, B2, 60 3 1 B3, C0, 1524 3 C2, A1/B1 30 12 3 60 6 2 60 12 3 120 6 2 60 24 3 120 12 3

TABLE 7 Another Possible Way of Determining Parameter k NUMBER OF RANDOMACCESS CHANNEL PHYSICAL RESOURCE Preamble BLOCKS (PER UL CHANNEL FormatΔf SUB CARRIER SPACING) k 0, 1, 2 15 6 7 30 3 1 60 2 133 3 15 24 11 3012 10 60 6 7 A0, A1, A2, 15 12 2 A3, B1, B2, 30 6 2 B3, C0, C2, 60 3 1A1/B1 15 24 2 30 12 2 60 6 2 60 12 2 120 6 2 60 24 2 120 12 2

TABLE 8 Yet Another Possible Way of Determining Parameter k NUMBER OFRANDOM ACCESS CHANNEL PHYSICAL RESOURCE Preamble BLOCKS (PER UL CHANNELFormat Δf SUBCARRIER SPACING) k 0, 1, 2 15 6 13 30 3 13 60 2 157 3 15 2413 30 12 13 60 6 13 A0, A1, A2, 15 12 3 A3, B1, B2, 30 6 3 B3, C0, C2,60 3 3 A1/B1 15 24 3 30 12 3 60 6 3 60 12 3 120 6 3 60 24 3 120 12 3

Hereinafter, a structure of a UE according to an embodiment of thedisclosure will be described with reference to FIG. 5.

FIG. 5 illustrates a structural block diagram of a UE according to anembodiment of the disclosure.

Referring to FIG. 5, a UE 500 may be used to perform the method 200 asdescribed with reference to FIG. 2. For the sake of brevity, only theschematic structure of the UE according to the embodiment of thedisclosure will be described herein, and details that have already beendescribed in the method 200 as previously described with reference toFIG. 2 will thus be omitted.

Referring to FIG. 5, the UE 500 includes a processing unit or processor501. The processor 501 may be a single unit or a combination of multipleunits for performing different operations of the method. The memory 502stores computer-executable instructions, which, when executed by theprocessor 501, cause the processor 501 to: obtain a random accesschannel subcarrier spacing Δf_(RA), a preamble length L_(RA) and a ULchannel subcarrier spacing Δf from a base station; and determine afrequency-domain offset parameter k of a preamble in a random accesschannel based on the obtained random access channel subcarrier spacingfΔ_(RA), preamble length L_(RA) and UL channel subcarrier spacing Δf.

As described above, the frequency domain offset parameter k of thepreamble in the random access channel may be calculated by the abovethree implementations as described previously, or may be obtained bylooking up a predefined correspondence table (e.g., one of the aboveTables 3-8) between the frequency-domain offset parameter k of thepreamble in the random access channel and the random access channelsubcarrier spacing Δf_(RA), the preamble length L_(RA), the UL channelsubcarrier spacing Δf. Reference may be made to the relevant descriptionof the method 200 as shown in FIG. 2.

Hereinafter, a method of generating a random access preamble basebandsignal will be described. As described in the foregoing embodiments ofthe disclosure, the random access baseband signal is generated using anequation as follows.

${s_{l}^{({p,\mu})}(t)} = {\sum\limits_{k = 0}^{L_{RA} - 1}{a_{k}^{({p,{PA}})} \cdot e^{j\; 2{\pi{({k + {Kk}_{0} + \overset{\_}{k}})}}\Delta\;{f_{RA}{({t - {N_{{CP},l}^{RA}T_{c}}})}}}}}$K = Δ f/Δ f_(RA)

where a_(k) ^((p,RA)) is a frequency-domain sequence generated for thepreamble, and is generated using an equation as follows.a _(k) ^((p,RA))=β_(PRACH) y _(u,v)(k)k=0,1, . . . ,L _(RA)−1

where β_(PRACH) is an amplitude adjustment factor obtained for powercontrol, which is used for allowing the transmitted signal to satisfy apower control constraint. y_(u,v)(k) is a frequency-domain signalobtained by transforming the preamble into the frequency domain, and isobtained by an equation as follows.

${{y_{u,v}(n)} = {\sum\limits_{m = 0}^{L_{RA} - 1}{{x_{u,v}(m)} \cdot e^{{- j}\frac{2\;\pi\;{mn}}{L_{RA}}}}}},$

where x_(u,v) (m) is a time-domain preamble.

As seen from the above description, following operations are required inorder to generate a baseband signal: discrete fourier transform (DFT)for generating a frequency-domain sequence y_(u,v)(n) from a time-domainpreamble x_(u,v)(m); subcarrier mapping for selecting a frequency-domainposition of the preamble based on a frequency-domain position of therandom access channel and a position of the preamble in the randomaccess channel; inverse discrete fourier transform (IDFT) for generatinga final time-domain baseband signal. The above operations may be shownin FIG. 6.

FIG. 6 illustrates a discrete fourier transform (DFT)-based basebandsignal generation method according to an embodiment of the disclosure.

Referring to FIG. 6, for some preamble formats, it needs to be repeatedin the time domain. A repeat module in FIG. 6 is used to generaterepeated preamble symbols.

Considering that in actual implementations, DFT and IDFT are generallyimplemented by fast fourier transform (FFT) and inverse fast fouriertransform (IFFT), and the number of FFT points is a power of 2, therewill be some problems in implementation if the above generation methodis used, since the random access channel subcarrier spacing does notmatch the UL data channel subcarrier spacing.

Specifically, for a case in which the UL channel subcarrier spacing isgreater than the random access subcarrier spacing, the IFFT used whenthe frequency-domain signal is transformed into the time-domain signalwill require a larger number of IFFT points. A simple example is a casein which the random access channel subcarrier spacing is 1.25 kHz andthe UL channel subcarrier spacing is 15 kHz. In order to meet thesampling interval specified in the protocol, 49152-point IFFT is needed,and 24576-point IFFT is needed even for the sampling interval in longterm evolution (LTE).

For a case in which the UL channel subcarrier spacing is smaller thanthe random access subcarrier spacing, using the UL channel subcarrierspacing directly may cause some waste.

One possible improved method includes: using the number of points ofIFFT determined according to the random access preamble length,determining the sampling interval of the time-domain samples accordingto the number of points of IFFT and the random access channel subcarrierspacing, and adjusting a sampling rate after a cyclic prefix is added.

The flowchart of the improved method is shown in FIG. 7.

FIG. 7 illustrates an improved preamble baseband signal generationmethod according to an embodiment of the disclosure.

Referring to FIG. 7, the number of points of IDFT is selected accordingto the preamble length. For example, for a preamble with a length of839, an IDFT of 1024 points is selected; and for a preamble with alength of 139, an IDFT of 512 points is selected.

The sampling interval in the time domain is selected based on the numberof points of IDFT and the frequency of the subcarrier of the randomaccess channel Particular selections are shown in Table 9 below.

TABLE 9 Selection of Time-Domain Sampling Frequency Time-Domain SamplingPreamble Random Access Channel Number of IDFT Frequency LengthSubcarrier Spacing (kHz) Points f_(RA) (MHz) 839 1.25 1024 1.28 839 51024 5.12 139 15 512 7.68 139 30 512 15.36 139 60 512 30.72 139 120 51261.44

A length of the cyclic prefix added subsequently should also be adjustedaccording to the above relationship between the required samplingfrequency and the final sampling frequency. The sampling frequency ofthe time-domain signal generated after IDFT is f_(RA), and the samplinginterval is T_(RA)=f_(RA), then the length of the added cyclic prefix isT_(CP)=N_(CP) ^(RA)T_(RA), where N_(CP) ^(RA) is the number of cyclicprefix points calculated according to the number of points of IDFT,which may be determined in advance according to the preamble format.

Considering that for all possible time-domain sampling intervals, nomaximum sampling frequency specified in 5G is exceeded, the subsequentsampling interval adjustments may upsample the time-domain signalsubjected to IDFT, possible time-domain repetition and addition of thecyclic prefix to generate a time-domain signal that meets the 5G systemrequirements.

Since there is no frequency-domain position selection in the foregoingprocess (in the flowchart as shown in FIG. 6, subcarrier selection isused), it is necessary to perform frequency-domain position adjustmenton the generated time-domain signal. Considering that thefrequency-domain position adjustment reflected in the time domain is aphase adjustment, the module performs phase adjustment on the generatedtime-domain signal.

In a specific example, if the first subcarrier of the preamble needs tohave a position offset of ϕ_(k) in the frequency domain, the signal at atime point t needs a phase adjustment amount of e^(j2πϕ) ^(k) ^(Δft). Ifthe effect of CP is considered, the phase adjustment amount should bee^(j2πϕ) ^(k) ^(Δf(t-N) ^(CP) ^(RA) ^(T) ^(c) ⁾, where T_(c) is a systemsampling rate. It should be noted that the frequency offset position inthis example is measured by the UL channel subcarrier spacing Δf. Iffrequency offset position in this example is measured by the randomaccess channel subcarrier spacing, the equation needs to be modified,and the phase adjustment amount at the time point t is e^(j2πKϕ) ^(k)^(Δf) ^(RA) ^(t). If the effect of CP is considered, the phaseadjustment amount is e^(j2πϕ) ^(k) ^(Δf(t-N) ^(CP) ^(RA) ^(T) ^(c) ⁾,where K=Δf/Δf_(RA).

In the foregoing example, the preamble is defined in the time domain, soit is required to firstly perform DFT to transform it into afrequency-domain signal. Another simple way is to use a frequency-domainsequence with a length L_(RA) directly, i.e., using a sequencey_(u,v)(k) or a sequence a_(k) ^((p,RA)) directly. In this case, aflowchart of generating a preamble baseband signal is shown in FIG. 8.

FIG. 8 illustrates method of generating a baseband signal according toan embodiment of the disclosure.

Referring to FIG. 8, in the existing 5G technology, if the systemselects the uplink of the 5G system according to the reference signalreceived power (RSRP) or supplementary uplinks to transmit the randomaccess preamble, the subsequent random access reattempt will further beperformed on the selected uplink. Since the failure of a random accessis likely to be caused by poor quality of the uplink channel used,restricting subsequent random access to reattempt on the same uplink asthe initial random access procedure will likely cause the subsequentrandom access procedure to continue to fail due to the quality problemof the uplink channel, thus affecting the system performance andaffecting the access experience of the terminal.

Moreover, in an existing 5G system, if there are multiple uplinkchannels in the system that may be used for random access procedure, andthe terminal selects one of the uplink channels for random accessprocedure according to the RSRP, then the subsequent random accessattempts will be performed on the uplink, which cannot avoid the problemthat random access procedure fails to be completed due to poor qualityof the selected uplink channel caused by measurement errors.

FIG. 9 illustrates a schematic flowchart of a random access methodaccording to an embodiment of the disclosure.

Referring to FIG. 9, based on the technical problems existing in theexisting 5G system described above, an embodiment of the disclosureprovides a random access method, as shown in FIG. 9, including operation910: performing a switching of an uplink if an uplink switchingcondition is met, when a random access is performed based on thedetermined uplink and the random access fails, and operation 920:performing a random access based on the after-switching uplink.

The embodiment of the disclosure provides a random access method. When arandom access is performed based on the determined uplink and the randomaccess fails, a switching is performed on the link if the uplinkswitching condition is met, so that it can be determined in time whetherthe uplink switching condition is satisfied when the random accessprocedure attempt fails, so as to determine whether to switching to theuplink with better channel condition to perform a random access.Moreover, the transmission is switched to the link when the uplinkswitching condition is met, which provides a precondition for asubsequent random access based on the after-switching link, and a randomaccess is performed based on the after-switching uplink, which enablesthe terminal to timely select the uplink with better channel quality toreattempt the random access procedure and perform a random access basedon the after-switching uplink when the random access attempt fails, thusreducing the delay of the random access and improving the overallperformance of the system.

In addition, according to the random access method provided by theimplementation of the disclosure, a switching may be performed betweenmultiple uplinks in the random access procedure, that is, when therandom access procedure attempt fails, it is possible to determine intime whether a switching is performed to the uplink with better channelcondition so as to obtain additional performance gain by the switchingbetween multiple uplinks. Moreover, by adopting the method provided bythe embodiment of the disclosure, when the initial random access attemptfails due to the poor quality of the initially selected uplink channelcaused by the initial measurement error, the terminal may timely selectthe uplink with better channel quality to reattempt the random accessprocedure, thereby reducing the delay of random access and improving theoverall performance of the system.

The random access method provided by the above implementation of thedisclosure will be described as follows:

In an implementation, when the random access based on the determineduplink is the initial random access, before the random access based onthe determined uplink, the method further includes:

acquiring a currently measured RSRP and at least one link selectionthreshold configured or preconfigured;

determining an uplink for an initial random access according to a resultof comparison between the RSRP and at least one link selectionthreshold.

In an implementation, when the total number of random access attempts isnot greater than the threshold of the total number of random accessattempts configured or preconfigured by the base station, it isdetermined whether the uplink switching condition is satisfied accordingto at least one of the following:

determining according to the result of comparison between the RSRPcurrently measured and at least one link selection threshold configuredor preconfigured;

determining according to the result of comparison between the RSRP andat least one link switching determination threshold; and

determining according to the result of comparison between the number ofrandom access attempts on the current uplink and the threshold of numberof random access attempts corresponding to the uplink.

In an implementation, the method of determining at least one linkswitching determination threshold includes at least one of thefollowing:

acquiring at least one link switching determination threshold configuredor preconfigured;

determining according to a first preset relationship configured and atleast one link selection threshold preconfigured, wherein the firstpreset relationship is a preset relationship between the link selectionthreshold and the link switching determination threshold.

In an implementation, the method of determining the threshold of numberof random access attempts corresponding to the uplink includes at leastone of the following:

acquiring the threshold of number of random access attemptscorresponding to the uplink configured or preconfigured; and

determining according to a configured second preset relationship and thepreconfigured threshold of total number of random access attempts,wherein the second preset relationship is a preset relationship betweenthe total number threshold of random access and the threshold of numberof random access attempts.

In an implementation, the random access configuration informationincludes at least one of random access channel configuration informationand random access preamble configuration information.

Wherein the random access is performed based on the random accessconfiguration information, including at least one of the followingsituations:

determining the time-frequency resources of the random access channel onthe after-switching uplink according to the configured random accesschannel configuration information, and performing a random access basedon the time-frequency resources of the random access channel and thecorresponding preconfigured random access preamble;

determining a preamble for random access on the after-switching uplinkaccording to the configured random access preamble configurationinformation, and performing a random access based on the preamble andthe preconfigured time-frequency resources of the corresponding randomaccess channel; and

determining the time-frequency resources of the random access channelaccording to the configured random access channel configurationinformation, determining the preamble for random access on theafter-switching uplink according to the configured random accesspreamble configuration information, and performing a random access basedon the time-frequency resources of the random access channel and thepreamble.

In an implementation, before performing the random access based on therandom access configuration information, the method further includes:

adjusting at least one of the number of random access attempts, thenumber of times of power ramping, and the power control parameterscorresponding to the after-switching uplink.

FIG. 10 illustrates a schematic flowchart of a random access methodaccording to an embodiment of the disclosure.

Referring to FIG. 10, at the same time, another embodiment of thedisclosure provides a method for configuring random access information,including: operation 1010: determining relevant configurationinformation for performing random access on at least two uplinksrespectively, wherein the configuration information includes informationfor performing a switching between at least two uplinks. Operation 1020:transmitting relevant configuration information.

The random access method provided by the above embodiment of thedisclosure determines relevant configuration information for performingrandom access on at least two uplinks respectively, and theconfiguration information includes information for performing aswitching between at least two uplinks, which provides a prerequisiteguarantee for the terminal to be able to perform random access onmultiple uplinks and a switching between multiple uplinks. Relevantconfiguration information is transmitted so that the terminal canperform a corresponding random access on multiple uplinks according tothe configuration information when performing the random access.

The random access method provided by the implementation of thedisclosure will be described as follows:

In an implementation, the information for performing a switching betweenat least two uplinks includes at least one of the following:

at least one link selection threshold;

at least one link switching determination threshold;

a first preset relationship between the link selection threshold and thelink switching determination threshold;

thresholds of random access attempts corresponding to at least twouplink respectively;

a second preset relationship between the threshold of total number ofrandom access attempts and each threshold of number of random accessattempts.

wherein the configuration information further includes at least one ofthe following:

random access configuration information for performing random access onat least two uplinks respectively; and

the threshold of total number of random access attempts.

In an implementation, the random access configuration informationincludes at least one of random access channel configuration informationand random access preamble configuration information.

The operation of determining random access configuration information forperforming random access on at least two uplinks respectively includesany of the following ways:

configuring a same random access channel configuration information and asame random access preamble configuration information for at least twouplinks;

configuring different random access channel configuration informationand different random access preamble configuration information for atleast two uplink configuration respectively;

configuring different random access channel configuration informationand a same random access preamble configuration information for at leasttwo uplink configuration respectively; and

configuring a same random access channel configuration information anddifferent random access preamble configuration information for at leasttwo uplink configuration respectively.

In particular, aiming at the technical problem that it cannot perform aswitching between random access channels on multiple available uplinksin the 5G prior art, and the random access method provided by theembodiment of the disclosure may perform a switching between multipleuplink random access channels, wherein the basic working principle ofthe random access method provided by the embodiment of the disclosure isas follows:

When the random access attempt fails, the terminal determines whetherthe uplink switching condition is met. If the uplink switching conditionis met, the uplink is switched, and the subsequent random accessreattempt is performed on a new after-switching uplink. If the uplinkswitching condition is not met, the subsequent random access reattemptcontinues on the current uplink. Wherein if the terminal performs aswitching of the uplink, the terminal adjusts the configuration andparameters of the random access procedure according to the correspondingconfiguration information of the new after-switching uplink, and thenthe terminal selects a random access channel and a preamble on theafter-switching new uplink according to the new configuration andparameters. Finally, the terminal initiates a random access reattempt onthe new after-switching uplink and transmits a preamble on the randomaccess channel of the selected uplink.

Hereinafter, the above embodiments of the disclosure will be fully andthoroughly described through the following several preferredimplementations:

Embodiment 1

In this embodiment of the disclosure, a switching method of a randomaccess channel in a multi-uplink system will be introduced incombination with a specific system. Assuming that there are multipleuplinks in the system, when the terminal performs initial random accessprocedure, it may select one of these multiple uplinks to perform arandom access procedure according to RSRP.

The terminal reads the system information transmitted in masterinformation block (MIB) or RMSI and determines the random accessconfiguration information, including the random access channelconfiguration information and the random access preamble configurationinformation. At the same time, the system information further includesthreshold information for determining the uplink. Wherein the thresholdinformation is a single threshold or a threshold set consisting ofmultiple thresholds for determining an uplink for random access.

Specifically, for a system in which there are two available uplinksconsisting of uplink 1 and uplink 2, the threshold 1 configured orpreconfigured by the base station for determining the uplink istransmitted in the system information. The terminal compares RSRP withthe threshold 1, and if RSRP is less than the threshold 1, the uplink 1is selected for random access. Otherwise, the uplink 2 is selected forrandom access.

For a system of K (K>2) available uplinks with uplink 1, . . . , uplinkK, the threshold set {η₁,upη_((K-1))} configured or preconfigured by thebase station is transmitted in the system information. The terminalcompares RSRP with the threshold in the threshold set, and ifη_((k-1))≤RSRP<η_(k), the uplink k is selected, wherein 1≤k≤K−1. If theRSRP>η_((K-1)), then the uplink K is selected.

Assuming that the terminal selects the uplink k for random accessprocedure according to the RSRP, the terminal determines thetime-frequency resources of the random access channel according to therandom access configuration information in the system information andaccording to the synchronization signal block selected by the RSRP, andrandomly selects a preamble with equal probability among the availablepreambles according to the random access preamble configurationinformation.

The terminal transmits the selected preamble on the time-frequencyresources of the random access channel on the selected uplink tocomplete the transmission of the preamble.

Due to measurement problems or channel quality problems, the randomaccess procedure performed by the terminal selecting uplink k may fail,for example, a random access response cannot be detected. Or, a randomaccess response is detected, but the preamble identifier containedtherein does not match the transmitted preamble. Or, the random accessresponse is successfully detected, and the preamble identifier thereinmatches the transmitted preamble, but the transmission of message 3times out. Or the terminal identification in the conflict resolutionresponse received after transmitting message 3 does not match. After thefailure of the random access procedure, the terminal will perform powerramping and try a random access again with new power.

For the problem that the random access attempts of the terminal continueto fail due to poor channel quality, it is possible to introduce aswitching between the uplinks. Specifically, if the previous randomaccess attempt fails, the uplink for the subsequent random accessattempt may be selected for switching. The brief process is as follows:

the random access of the terminal fails previously;

the terminal determines the link switching condition;

if the link switching condition is met, performing a switching to a newuplink and reattempting a random access; otherwise, reattempting arandom access on the current link.

Wherein, the above flow may be briefly described with the flow chartshown in FIG. 11.

FIG. 11 illustrates a schematic diagram of a basic process of a randomaccess method according to an embodiment of the disclosure.

Referring to FIG. 11, it should be noted that the implementation premiseof the uplink switching procedure is that the total number of randomaccess attempts performed by the terminal does not exceed the maximumnumber of random access attempts configured or preconfigured by the basestation (i.e., the threshold of total number of random access attemptsconfigured or preconfigured by the base station, e.g., N_(max)).

The above uplink switching condition may be as follows:

1. The Terminal Uses the RSRP as the Uplink Switching Condition.

Specifically, one possible way is that the terminal periodicallyperforms uplink measurements and compares the measurement results (i.e.,RSRP) with the previously configured or preconfigured thresholds orthreshold sets. If it is found that the RSRP measured last time nolonger meets the condition for selecting the current link, it isconsidered that the link switching condition is met, a new uplink isselected, and a new random access procedure attempt is performed.Otherwise, it is considered that the link switching condition is notmet, and the random access procedure attempt on the current uplink willcontinue. When the random access attempt fails, the terminal selects anew uplink according to the RSRP measured last time and the configuredor preconfigured threshold or threshold set mentioned above, andperforms a random access procedure reattempt on the new uplink.

A simple example is as follows:

In the initial random access procedure attempt, the terminal selects theuplink k according to the aforementioned uplink selection criteria. Whenthe uplink random access procedure fails (including the case of multiplefailures), the terminal performs uplink measurement and finds that themeasurement result (RSRP) no longer meets the selection condition ofuplink k, then it is considered as triggered uplink switching. Theterminal selects a new uplink according to the RSRP and the previouslyconfigured or preconfigured threshold set. For example, the terminalselects uplink q for subsequent random access attempts if the terminalobtains {η_(q-1)≤RSRP<η_(q)} according to the RSRP and the comparisonbetween the threshold sets.

It should be noted that the above measurement results are the downlinkmeasurements, and the corresponding uplink is selected based on the RSRPobtained from the downlink measurements.

Another possible way is for the base station to configure orpreconfigure another threshold or threshold set for the determination ofuplink switching. Specifically, if there are two uplinks, the threshold2 is configured or preconfigured. If the uplink that was previouslyselected is less than the threshold 1, the link switching condition isthat the last measurement result (RSRP) is not less than the threshold2. If the uplink that was previously selected is not less than thethreshold 1, the link switching condition is that the last measurementresult is greater than the threshold 2.

If there are K uplinks, a threshold set {δ₁, . . . , δ_(K-1)} for uplinkswitching determination is configured or preconfigured, that is, a linkswitching determination threshold set {δ₁, . . . , δ_(K-1)} is defined.Specifically, if the uplink k (k<K) was selected last time, then theswitching determination condition is that the RSRP measured last timedoes not meet δ_(k-1)≤RSRP<δ_(k). If this condition is not met, then theuplink switching is performed, otherwise, subsequent random accessprocedure attempts are performed on the current link. If the uplink Kwas previously selected, the switching determination condition is thatRSRP≥δ_(K-1) should be met. If this condition is not met, the uplinkswitching is performed, otherwise, subsequent random access procedureattempts are performed on the current link. In the above way, when theuplink is reselected, it may be based on the threshold set {η₁, . . . ,η_(K-1)} configured or preconfigured by the base station. At this time,{η₁, . . . , η_(K-1)} will be defined as the link selection thresholdset, while {δ₁, . . . , δ_(K-1)} will be defined as the link switchingdetermination threshold set. If the uplink is reselected, it may furtherbe based on the new threshold set {δ₁, . . . , δ_(K-1)} (i.e., the linkswitching determination threshold set).

In this method, the threshold or threshold set for determining uplinkswitching may be separately configured and informed in the RMSI, and mayfurther have a fixed relationship with the initially defined thresholdor threshold set. For example, parameters Δ are configured orpreconfigured in MIB or the RMSI to describe the relationship betweenthe threshold or threshold set (i.e., link switching determinationthresholds) for determining uplink switching and the initially definedthreshold or threshold set (i.e., link selection thresholds). Forexample, for a system consisting of two uplinks, the relationshipbetween threshold 1 and threshold 2 is:threshold 2=threshold 1+Δ

For a system consisting of k uplinks, the relationship between thethreshold set {δ₁, . . . , δ_(K-1)} and the threshold set {η₁, . . . ,η_(K-1)} is:δ_(k)=η_(k)+Δ

wherein, 1≤k≤K.

In this way, the parameters Δ may be configured together with theaforementioned thresholds or threshold set through the MIB or RMSI, orthe terminal may be informed in a predefined or preconfigured way. Theterminal determines a threshold or threshold set for uplink switchingaccording to the aforementioned method based on the preconfigured orconfigured threshold or threshold set and the preconfigured orconfigured parameters Δ.

In another possible way, when the random access procedure fails, thedownlink is measured to determine whether an uplink switching isrequired. The switching criteria in the two ways mentioned above may beused.

2. The Terminal Will Use the Number of Random Access Attempts on theSelected Uplink as the Switching Condition.

Specifically, the base station configures or preconfigures the maximumnumber of random access attempts performed on the selected uplinkM_(max) (i.e., the threshold of number of random access attemptscorresponding to the uplink). If the number of random access attemptsperformed on the uplink reaches the configured or predefined maximumnumber (i.e., the threshold of number of random access attempts), thenit is considered that the link switching condition is satisfied and theuplink switching will be performed.

Further, a possible way is to count random access attempts performed onthe selected uplink, and if the count reaches M_(max), a switching isperformed on the link. The random access attempts on the selected uplinkare counted, including the following ways:

(1) a separate counter may be set up for each uplink, and each counteris initialized to 1 when initializing a random access. For the selecteduplink for random access procedure, the counter corresponding to theuplink is used to count the number of random access attempts performedon the link. If the counter reaches M_(max), the link switching isperformed. After the uplink switching, the counter used in the originaluplink is reset to 0 or remains unchanged.

(2) a counter for uplink counting is established, in which the counteris initialized to 1 when initializing a random access, and the counterrecords the random access attempt performed by the uplink after anuplink random access attempt is selected. If the counter reachesM_(max), the link switching is performed. After the link switching, thecounter is reset to 1 and the number of random access attempts on thenew uplink is recorded.

For uplink reselection, a rule may be predefined: If the system includestwo uplinks, when the uplink is reselected, another uplink other thanthe current uplink is selected for the random access reattempt. If thesystem includes multiple uplinks, it may choose to reattempt the randomaccess procedure near the uplinks. For example, if the uplink k isselected, the uplink k−1 or the uplink k+1 will be selected when theuplink is reselected.

(3) if there are two available uplinks, the counter for uplink randomaccess may not be defined separately, but the transmission counter usedby the random access procedure may be used to determine the uplinkswitching. A simple method is that the terminal completes initializationof the random access procedure and selects the uplink 1 to make randomaccess attempts according to the measurement results. The terminaltransmits the preamble on the uplink 1 and starts counting of thetransmission counter. Until the transmission counter reaches M_(max),random access re-attempts caused by random access procedure failure areall performed on the uplink 1. If it is found that the transmissioncounter reaches M_(max) during the resource selection of random accessreattempt, the transmission is switched to the uplink 2, thetime-frequency resources of the random access channel and the preambleare selected according to the random access configuration information,and the subsequent random access reattempt is performed on the uplink 2.

For the case where there are only two uplinks in the system, the randomaccess attempt counter may be used instead of the counter for recordingrandom access attempts performed on the selected uplink. In this case,another criterion for determining whether to perform an uplink switchingis that if the value N of the random access attempt counter meets:mod(N,M _(max))=0

then an uplink switching is performed, otherwise, a reattempt of therandom access procedure is continued on the currently selected uplink.

The aforementioned parameters M_(max) of the number of attempts toperform the random access procedure on the selected uplink may beconfigured and informed in the MIB or RMSI, or may be configured in apredefined way. In other configuration way, the relationship between theparameters M_(max) (that is, the threshold of number of random accessattempts corresponding to the uplink) and the maximum total number oftimes of number of random access attempts N_(max) (that is, thethreshold of total number of random access attempts) configured orpreconfigured by the base station may be defined. For example, a simpleway is that the relationship between the parameters M_(Max) and N_(max)(which are configured or preconfigured by the base station) is:M _(max)=[N _(max) /K],

where K is an integer and the symbol [⋅] is a rounding operation, whichmay be replaced by rounding down or rounding up. The parameter k may beconfigured by a base station configuration or a predefined way, orconfigured and informed in the MIB or RMSI.

3. Combination of the Above Two Ways.

When a random access procedure attempt is performed on the selecteduplink, if the number of attempts reaches M_(max) (i.e., the thresholdof number of random access attempts corresponding to the uplink)configured or preconfigured by the base station, it is determinedwhether an uplink switching is necessary based on the last measurementresult.

For counting the number of times of random access procedure attempts onthe selected uplink, the method described in the aforementioned method 2may be used, i.e., counting each uplink setting counter, or setting anuplink counter, which is set to zero when the uplink switching isperformed. For a system with only two uplinks, the random accessprocedure counter may be used instead of the uplink counter. The settingof parameters M_(max) may be informed by configuration orpre-configuration of the base station, or may be informed or configuredindirectly by the base station which configures or preconfigures therelationship of the M_(max) and the maximum total number of randomaccess attempts N_max.

If the number of random access attempts performed on the selected uplinkreaches M_(max), the latest measurement result (for example, RSRP) iscompared with the threshold or threshold set configured or preconfiguredby the base station to determine whether the uplink switching isrequired. The configuration and notification of the threshold orthreshold set configured or preconfigured by the base station may adoptthe way in the aforementioned method 1.

If the number of attempts reaches M_(max) and the latest measurementresult meets the uplink switching condition, then a new uplink may beselected for switching using the criteria in the aforementionedmethod 1. If the number of attempts reaches M_(max), but the latestmeasurement result does not meet the uplink switching condition, then anuplink switching is not performed, then the counter used to performrandom access attempt counting on the selected uplink may be reset to 1or no additional processing will be performed on the counter.

For the case where there are only two uplinks in the system, the randomaccess attempt counter may be used instead of the counter for recordingrandom access attempts performed on the selected uplink. In this case,another criterion for determining whether to perform the uplinkswitching is that if the value N of the random access attempt countermeets:mod(N,M _(max))=0

Then it is determined whether the uplink switching is necessaryaccording to the latest measurement result. Wherein the counter N iscounted whether the link switching is performed or not.

Embodiment 2

In the second embodiment, a method of random access procedure uplinkswitching will be introduced in combination with a specific system.Embodiment 1 shows a general example, and this embodiment will explainan uplink switching method in combination with the case where there areboth a common uplink and a supplementary uplink in a 5G system.

In the second embodiment, it is assumed that there are two uplinks inthe system, in which one is a common uplink for normal uplink datatransmission of the system, and the other is a supplementary uplink,which is used to provide an uplink channel for terminals with poorchannel quality so as to facilitate access and data transmission ofthese terminals. The base station configures random access channelconfiguration information, random access preamble configurationinformation, and threshold configuration information in the MIB or RMSIto determine whether to perform a random access attempt on thesupplementary uplink.

After receiving the configuration information, the terminal compares theRSRP measured on the downlink with the threshold, and if the RSRP isless than the threshold, selects to perform a random access attempt onthe supplementary uplink. If the RSRP is not less than the threshold,the terminal selects to perform a random access attempt on the commonuplink. For the random access attempt performed on the supplementaryuplink, subsequent random access reattempts caused by failure of arandom access will further be performed on the supplementary uplink,while the random access attempt on the common uplink may trigger anuplink switching when the random access attempt fails, a switching isperformed to the supplementary uplink to continue a subsequent randomaccess reattempt.

The following content mainly discusses the process of selecting theinitial random access procedure to be performed on the common uplink anda switching being performed to the supplementary uplink during thesubsequent random access reattempt.

If the random access attempt fails in the random access procedure on thecommon uplink and the number of random access attempts does not exceedthe maximum number of random access attempts configured by the system,it is determined whether the uplink switching condition is met. If theuplink switching condition is met, a switching is performed to thesupplementary uplink, and subsequent random access reattempts are allperformed on the supplementary uplink. If the uplink switching conditionis not met, the random access reattempt continues on the common uplink.

Similar to Embodiment 1, the uplink switching condition may be in thefollowing ways:

1. The Terminal Periodically Measures the Downlink, for Example,Measures a Synchronization Signal Block of the Downlink to Obtain aCorresponding RSRP.

If the random access attempt fails, the terminal compares the last RSRPwith the link selection threshold η configured or preconfigured by thebase station for selecting the uplink. If the RSRP<η, it is consideredthat the current common uplink is no longer suitable for the randomaccess attempt of the terminal, and the next random access reattemptwill be performed on the supplementary uplink. If RSRP≥η, the nextrandom access reattempt is still performed on the common uplink.

In another way, when the base station configures or preconfigures a linkswitching determination threshold δ for determining whether to perform aswitching of the uplink, meanwhile the random access attempt performedon the common uplink fails, and the number of random access attemptsdoes not exceed the maximum number configured or preconfigured by thebase station, the last measured RSRP is compared with the link switchingdetermination threshold δ for determining the uplink switching, and ifthe RSRP<δ, the next random access reattempt will be performed byswitching to the supplementary uplink. If the RSRP≥δ, the next randomaccess reattempt will be performed on the common uplink.

It should be noted that the newly defined link switching determinationthreshold δ for determining whether the uplink is switched may beconfigured and informed by the base station in MIB or RMSI, or may beconfigured and informed by configuring or preconfiguring therelationship between the link switching determination threshold δ andthe link selection threshold q for initially selecting the uplink.Specifically, parameters Δ may be preconfigured or configured andinformed, and a link switching determination threshold δ for determiningwhether the uplink is switched according to the following relationship:δ=η+Δ

In another method, if the random access attempt performed by theterminal on the common uplink fails, the downlink is measured, andwhether uplink switching is required is determined based on thecomparison of the RSRP measured this time with the threshold configuredor preconfigured by the base station.

2. An Uplink Switching is Determined Whether to be Required According tothe Number of Random Access Attempts on the Common Uplink.

Specifically, a counter for counting the number of random accessattempts is used and a parameter M_(max) (i.e., a threshold of number ofrandom access attempts corresponding to the uplink) is preconfigured. Ifthe random access attempt fails and the counter for counting the numberof random access attempts reaches M_(max), the next random accessreattempt will be performed by switching to the supplementary uplink.

3. The Combination of the Above Two Ways. For Example, when the RandomAccess Attempts Performed on the Common Uplink Reaches the Preconfiguredor Configured Number, the Last Downlink Measurement Result (RSRP) isCompared with the Preconfigured Threshold, and if the Link SwitchingCondition is Met, the Subsequent Random Access is Performed on theSupplementary Uplink. Otherwise, the Next Random Access ProcedureReattempt Will be Performed on the Common Uplink.

Specifically, the base station may configure or preconfigure theparameter M to determine whether to perform an uplink switching once forevery M attempts in the random access procedure on the common uplink.

One implementation is to configure or preconfigure a test intervalcounter, which is initialized to 1 when the random access procedure isinitialized, and is incremented every time the random access attemptfails and determined whether the counter reaches M or not. If thecounter does not reach M, the next random access reattempt is stillperformed on the common uplink. If the counter reaches M, it isdetermined whether to perform a link switching or not according to theRSRP obtained from the latest measurement and the threshold configuredor preconfigured by the base station.

Another implementation is to directly use the counter value N forrecording the number of random access attempts. If the random accessprocedure performed on the common uplink fails and the random accessattempt number counter does not reach the maximum number of attemptsconfigured or preconfigured by the base station, then:

If mod(N,M)≠0, the next random access reattempt continues on the commonuplink.

If mod(N,M)=0, it is determined whether a link switching is requiredaccording to the RSRP measured recently and the preconfigured orconfigured threshold.

Wherein the parameter M may be configured or preconfigured by the basestation or has a fixed relationship with the maximum number N_(max) ofrandom access attempts configured or preconfigured by the base station,for example, M=[N_(max)/K]. Where K is an integer, the roundingoperation in the above equation may be replaced by rounding down orrounding up. K may be configured and informed by the base station in theMIB or RMSI or set in a predetermined way.

In the above method, the method described in method 1 in this embodimentmay be used to determine whether the uplink is switched by the RSRP andthe preconfigured or configured threshold.

Embodiment 3

In this embodiment, an uplink switching method of a random accessprocedure will be introduced in combination with a specific system. Theswitching criteria for the terminal to perform on uplink in multipleuplinks are introduced in Embodiment 1 and Embodiment 2, and thecorresponding random access method after performing an uplink switchingwill be introduced in this embodiment.

When performing a random access procedure on a system supportingmultiple uplinks, the terminal first selects an appropriatesynchronization signal block according to the measurement result (RSRP),and reads random access configuration information in MIB or RMSI,including random access channel configuration information, random accesspreamble configuration information, and threshold information forselecting an uplink.

The terminal selects the uplink for performing the random accessprocedure according to the RSRP and threshold information, obtains thetime-frequency resources of the random access channel in the uplink fromthe random access configuration information, and selects the randomaccess preamble. The terminal transmits a preamble on a random accesschannel on the selected uplink.

The terminal performs random access attempts on the selected uplink, andif the random access attempts fail and the number of random accessattempts does not reach the maximum number of random access attemptsconfigured or preconfigured by the base station, it is determinedwhether an uplink switching is required. Whether an uplink switching isrequired may be performed in the manner described in embodiments 1 and2. If the uplink switching is not performed, the random access attemptscontinue on the current uplink.

If the uplink switching is performed, it is necessary to perform aswitching to a new uplink and continue random access attempts. If anuplink switching is required, some parameters and configuration of therandom access procedure need to be adjusted. The parameters andconfiguration that need to be adjusted include: a preamble transmissionnumber counter, a power ramping counter, random access channelconfiguration, preamble configuration, etc.

1. Preamble Transmission Number Counter

This counter is used to count the number of random access attemptsperformed by the terminal. Possible behaviors of the preambletransmission number counter when an uplink switching occurs include:

1a. keep unchanged, that is, the uplink switching does not affect thecounting of the number of the preamble transmissions, which is stillcounted according to a normal random access procedure.

1b. reset, that is, the number of the preamble transmissions isreinitialized to 1 after the uplink switching. In this processing way,one possible subsequent processing is to reset only the number of thepreamble transmissions to 1, but does not affect the selection andprocessing of other parameters and configuration. Another possiblefollow-up processing is to reinitialize the entire random accessprocedure, reset the power ramping counter to 1, and reselect thetime-frequency resources of the random access channel and the randomaccess preamble according to the random access configurationinformation.

2. Power Ramping Counter

This counter is used to compute the power ramping during a random accessreattempt. Possible behaviors of the power ramping counter when anuplink switching occurs include:

2a. keep unchanged, that is, the uplink switching does not affect thecounting of the power ramping counter, which is still counted accordingto a normal random access procedure.

2b. reset, that is, the counting of the power ramping counter is resetto 1 after the uplink switching.

3. Random Access Configuration Information

If different uplinks use uniform random access configurationinformation, the terminal does not need to adjust the random accessconfiguration information when performing a switching on the uplink, andonly needs to select the time-frequency resources of the random accesschannel on the after-switching uplink according to the random accesschannel configuration information contained in the random accessconfiguration information.

If the random access configuration information used by different uplinksis different, random access configuration information, including randomaccess channel configuration information and random access preambleconfiguration information of each link, is respectively configured foreach uplink in the RMSI or MIB. After a switching is performed to a newuplink, corresponding random access configuration information isselected on the selected uplink according to the random accessconfiguration information corresponding to the selected uplink, andtime-frequency resources of the random access channel are determined. Inaddition, a preamble with equal probability is selected from the randomaccess preamble resource pool according to the random access preambleinformation, and the selected preamble is transmitted on thetime-frequency resources of the random access channel on the selecteduplink.

For the case that the random access configuration information used bydifferent uplink is not the same, it further includes the uniformconfiguration of part of the configuration information and the separateconfiguration of part of the configuration information for differentuplinks. For example, one possible way is as follows: different uplinksuse uniform random access channel configuration information and usedifferent random access preamble configuration information. At thistime, the terminal selects time-frequency resources of the random accesschannel on the newly selected uplink after switching according to theuniform random access channel configuration information, and randomlyselects a preamble from the corresponding preamble resource pool withequal probability according to the selected uplink and the preambleconfiguration information corresponding to the uplink. Thereafter, theterminal transmits the preamble on the random access channel on theselected uplink.

Another possible way is to use uniform preamble configurationinformation and different random access channel configurationinformation for different uplinks. At this time, the terminal randomlyselects a preamble with equal probability from the correspondingpreamble resource pool according to the uniform preamble configurationinformation, and determines the time-frequency resources of the randomaccess channel on the selected uplink according to the selected uplinkand the random access channel configuration information corresponding tothe uplink. Thereafter, the terminal transmits the preamble on therandom access channel on the selected uplink.

It should be noted that the random access channel configurationinformation in the above description includes information of thetime-frequency resources of the random access channel, subcarrierspacing, preamble format information, etc. The preamble configurationinformation includes sequence generation information, such as rootsequence configuration information and cyclic shift configurationinformation.

4. Power Configuration

Different uplink random access procedures may use different powercontrol parameters, for example, different uplink may use differenttarget reception powers and power ramping parameters. Power controlparameters of different uplinks may be configured and informed in MIB orRMSI. When the switching is performed for the terminal to a new uplinkand the preamble is prepared to be transmitted, the transmission powerof the preamble is computed according to the power control configurationparameters (such as target reception power and power ramping parameters)corresponding to the selected uplink and the value of the power rampingcounter, and the transmission power of the preamble is adjustedaccording to the parameters.

It should be noted that the above four configuration parameters that maybe adjusted during uplink switching may be used in combination.

A special example of this embodiment is a system that includes both acommon uplink and a supplementary uplink in a 5G system. The commonuplink is used for the normal uplink data transmission of the system,while the supplementary uplink is used for providing uplink channels forterminals with poor channel quality so as to facilitate the access anddata transmission of these terminals. When configuring and notifying therandom access configuration information, the base station may onlyconfigure or preconfigure one random access configuration information,including random access channel configuration information, random accesspreamble configuration information, and threshold information forselecting an uplink. For example, when configuring and notifying therandom access configuration information, the base station may onlyconfigure the random access channel configuration information, andpre-configure the random access preamble configuration information, orthe base station may only configure the random access preambleconfiguration information and pre-configure the random access channelconfiguration information. In addition, the base station may furtherconfigure both the random access channel configuration information andthe random access preamble configuration information.

When transmitting the configuration information, the base station mayonly configure or preconfigure a set of random access configurationinformation. In this case, the common uplink and the supplementaryuplink use the same random access configuration information configuredor preconfigured by the base station. The base station may configure orpreconfigure two sets of random access configuration information, oneset for random access procedure on the common uplink and one set forrandom access procedure on the supplementary uplink. The terminalselects the uplink that initiates the random access procedure throughthe measurement of the downlink and the threshold information configuredor preconfigured by the base station, and selects the random accesschannel and the random access preamble according to the random accessconfiguration information of the corresponding link.

If the terminal selects the common uplink for random access attemptduring initialization, but triggers the uplink switching conditionduring the random access procedure attempt, a switching will beperformed for the terminal to the supplementary uplink for subsequentrandom access procedure reattempts. The parameters and configurationinformation of the random access procedure will be adjusted during theswitching, including: preamble transmission number counter, powerramping counter, random access channel configuration, preambleconfiguration, etc. The adjustment of these parameters and configurationinformation may be performed in the manner described above in thisembodiment.

It should be noted that the random access procedure in the embodiment ofthe disclosure may be a competition-based random access procedure or acompetition-free random access procedure. For the contention-free randomaccess procedure, both the random access channel and the random accesspreamble may be directly configured by the base station. The randomaccess channel and the preamble on the two uplinks may be configured tobe the same or different.

The downlink measurement information described in the disclosure may beobtained by measuring a synchronization signal block. Specifically, thesynchronization signal block within the synchronization signal blockperiod in the cell is measured to obtain the corresponding RSRP and theaverage value to serve as the RSRP of the measurement result. Forexample, the measurement result in this case is the average RSRP. Inanother way, the synchronization signal block selected by the terminalmay be measured, and the RSRP measured by the synchronization signalblock is used as the RSRP for determining whether a switching isperformed for the uplink or not.

For a terminal in a synchronous state, a channel state informationreference signal (CSI-RS) may be used for measurement, and the obtainedRSRP may be used as a basis for determining whether a switching isperformed for the uplink or not. Specifically, CSI-RSs corresponding toall downlink beams may be measured, the RSRP obtained may be averaged,and the average RSRP may be used as the basis for determining whether aswitching is performed for the uplink or not. Or, the CSI-RS selected bythe terminal/configured by the base station is measured, and the RSRPobtained by measurement is directly used.

Based on the above description, it may be seen that the random accessmethod provided in the embodiment of the disclosure may perform anuplink switching in a random access procedure. Wherein, a new uplink isselected, when the random access procedure fails and a random accessreattempt is to be initiated, through the measurement of the downlink.Moreover, the method provided by the embodiment of the disclosure issuitable for the situation that multiple uplinks exist in the system,and may effectively avoid the problem that the random access procedurecontinues to fail due to poor quality of the selected uplink channelwhen multiple uplinks exist in the system. At the same time, the methodfurther avoids the problem of significant interference to otherterminals that need to be accessed due to the high power ramping causedby multiple attempts on the same uplink.

Another embodiment of the disclosure provides a terminal device, asshown in FIG. 12, including: A switching module 121 and an access module122, wherein the switching module 121 is configured to perform aswitching on the uplink if the uplink switching condition is satisfiedwhen a random access is performed based on the determined uplink and therandom access fails. The access module 122 is configured to perform arandom access based on the after-switching uplink.

FIG. 12 illustrates a schematic diagram of a basic structure of aterminal device according to an embodiment of the disclosure.

Referring to FIG. 12, specifically, when the threshold of total numberof random access attempts is not greater than the configured orpreconfigured number of random access thresholds, the switching module121 is specifically configured to determine whether the uplink switchingcondition is satisfied according to at least one of the following:determining according to the result of comparison between the RSRPcurrently measured and at least one link selection threshold configuredor preconfigured; determining according to the result of comparisonbetween the RSRP and at least one link switching determinationthreshold; and determining according to the result of comparison betweenthe number of random access attempts on the current uplink and thethreshold of number of random access attempts corresponding to theuplink.

Further, the way in which the switching module 121 determines at leastone link switching determination threshold includes at least one of thefollowing: acquiring at least one link switching determination thresholdconfigured or preconfigured; determining according to a first presetrelationship configured and at least one link selection thresholdpreconfigured, wherein the first preset relationship is a presetrelationship between the link selection threshold and the link switchingdetermination threshold.

Further, the way in which the switching module 121 determines thethreshold of number of random access attempts corresponding to theuplink includes at least one of the following: acquiring the thresholdof number of random access attempts corresponding to the uplinkconfigured or preconfigured; determining according to a configuredsecond preset relationship and the preconfigured threshold of totalnumber of random access attempts, wherein the second preset relationshipis a preset relationship between the threshold of total number of randomaccess attempts and the threshold of number of random access attempts.

Further, the access module 122 is specifically configured to acquirerandom access configuration information corresponding to theafter-switching uplink; and perform a random access based on the randomaccess configuration information.

Further, when the random access configuration information includes atleast one of random access channel configuration information and randomaccess preamble configuration information, the access module 122 isspecifically configured to in at least one of the following situations:determine the time-frequency resources of the random access channel onthe after-switching uplink according to the configured random accesschannel configuration information, and perform a random access based onthe time-frequency resources of the random access channel and thecorresponding preconfigured random access preamble; determine a preamblefor random access on the after-switching uplink according to theconfigured random access preamble configuration information, and performa random access based on the preamble and the preconfiguredtime-frequency resources of the corresponding random access channel; anddetermine the time-frequency resources of the random access channelaccording to the configured random access channel configurationinformation, determine the preamble for random access on theafter-switching uplink according to the configured random accesspreamble configuration information, and perform a random access based onthe time-frequency resources of the random access channel and thepreamble.

Further, the access module 122 is further configured to adjust at leastone of the number of random access attempts, the number of times ofpower ramping, and the power control parameters corresponding to theafter-switching uplink before performing random access based on therandom access configuration information.

The embodiment of the disclosure provides a random access method. When arandom access is performed based on the determined uplink and the randomaccess fails, if the uplink switching condition is met, a switching isperformed on the link, so that when the random access procedure attemptfails, whether the uplink switching condition is satisfied is determinedin time, so as to determine whether a switching may be performed to theuplink with better channel condition so as to perform a random access.Moreover, when the switching condition of the uplink are met, aswitching is performed on the link, which provides a prerequisiteguarantee for the subsequent random access based on the after-switchinglink, and a random access is performed based on the after-switchinguplink. In this way, when the random access attempt fails, the terminalmay timely select the uplink with better channel quality to perform arandom access procedure reattempt, and a random access is performedbased on the after-switching uplink, thus reducing the delay of randomaccess and improving the overall performance of the system.

Yet another embodiment of the disclosure provides a base station, asshown in FIG. 13, including a determination module 131 and atransmission module 132. Wherein the determination module 131 isconfigured to determine relevant configuration information forperforming random access on at least two uplinks, the configurationinformation including information for performing a switching between atleast two uplinks. The transmission module 132 is configured to transmitthe configuration information.

FIG. 13 illustrates a basic structural diagram of a base stationaccording to an embodiment of the disclosure.

Referring to FIG. 13, specifically, the information for performing aswitching between at least two uplinks determined by the determinationmodule 131 includes at least one of the following: at least one linkselection threshold; at least one link switching determinationthreshold; a first preset relationship between the link selectionthreshold and the link switching determination threshold; thresholds ofrandom access attempts corresponding to at least two uplinksrespectively; and a second preset relationship between the threshold oftotal number of random access attempts and each threshold of number ofrandom access attempts. The configuration information further includesat least one of the following: random access configuration informationfor performing random access on at least two uplinks respectively; andthe threshold of total number of random access attempts.

Further, the random access configuration information includes at leastone of random access channel configuration information and random accesspreamble configuration information. The determination module 131determines random access configuration information for performing randomaccess on at least two uplinks, including any of the following ways:

configuring the same random access channel configuration information andthe same random access preamble configuration information for at leasttwo uplinks;

configuring different random access channel configuration informationand different random access preamble configuration information for atleast two uplink configuration respectively;

configuring different random access channel configuration informationand the same random access preamble configuration information for atleast two uplink configuration respectively; and

configuring the same random access channel configuration information anddifferent random access preamble configuration information for at leasttwo uplink configuration respectively.

In the embodiment of the disclosure, relevant configuration informationfor performing random access on at least two uplinks is determined, andthe configuration information includes information for performing aswitching between at least two uplinks, which provides a prerequisiteguarantee for the terminal to be able to perform random access onmultiple uplinks and a switching between multiple uplinks. Theconfiguration information is transmitted so that the terminal canperform a corresponding random access on multiple uplinks according tothe configuration information when performing the random access.

Yet another embodiment of the disclosure provides a terminal deviceincluding a processor; and a memory configured to store machine-readableinstructions that, when executed by the processor, cause the processorto perform the random access method described above.

Yet another embodiment of the disclosure provides a base stationincluding a processor; and a memory configured to store machine-readableinstructions that, when executed by the processor, cause the processorto perform the method for configuring random access information.

FIG. 14 illustrates a block diagram of a computing system that may beused to implement a base station or UE of the disclosure according to anembodiment of the disclosure.

Referring to FIG. 14, a computer system 1400 includes a processor 1410,a computer readable storage medium 1420, an output interface 1430, andan input interface 1440. The computing system 1400 may perform themethod described above with reference to FIG. 9 or FIG. 10 to configurea reference signal and perform data transmission based on the referencesignal.

Specifically, the processor 1410 may include, for example, a generalpurpose microprocessor, an instruction set processor, and/or anassociated chipset and/or an application specific microprocessor (e.g.,an application specific integrated circuit (ASIC)), etc. The processor1410 may further include an on-board memory for caching purposes. Theprocessor 1410 may be a single processing unit or multiple processingunits for performing different actions of the method flow described withreference to FIG. 9 or FIG. 10.

The computer readable storage medium 1420 may be, for example, anymedium capable of containing, storing, transmitting, propagating, ortransmitting instructions. For example, readable storage media mayinclude, but are not limited to, electrical, magnetic, optical,electromagnetic, infrared, or semiconductor system, apparatus, devices,or propagation media. Specific examples of the readable storage mediainclude: a magnetic storage device, such as a magnetic tape or a harddisk (hard disk drive (HDD)), an optical storage device, such as anoptical disc (compact disc (CD)-read only memory (ROM)); memory, such asa random access memory (RAM) or a flash memory; and/or wired/wirelesscommunication links.

The computer readable storage medium 1420 may include a computer programthat may include code/computer executable instructions that, whenexecuted by the processor 1410, cause the processor 1410 to perform, forexample, the method flow described above in connection with FIG. 9 orFIG. 10 and any variations thereof.

The computer program may be configured to have computer program codeincluding, for example, a computer program module. For example, in anexample embodiment, the code in the computer program may include one ormore program modules, including, for example, module 1, module 2 . . . .It should be noted that the division mode and number of modules are notfixed, and those skilled in the art may use suitable program modules orprogram module combinations according to the actual situation. Whenthese program module combinations are executed by the processor 1410,the processor 1410 may perform, for example, the method flow describedabove in connection with FIG. 9 or FIG. 10 and any variations thereof.

According to an embodiment of the disclosure, the processor 1410 may usethe output interface 1430 and the input interface 1440 to execute themethod flow described above in connection with FIG. 9 or FIG. 10 and anyvariations thereof.

In accordance with an aspect of the disclosure, a method by terminal isprovided. The method includes receiving, from a base station, firstinformation related to a length of a random access preamble and a firstsubcarrier spacing of a random access channel, receiving, from the basestation, second information related to a second subcarrier spacing of aphysical uplink shared channel (PUSCH), identifying an offset parameterbased on the length of the random access preamble, the first subcarrierspacing, and the second subcarrier spacing, the offset parameter beingused to identify a frequency resource of the random access channel, andtransmitting the random access preamble based on the offset parameter.

In accordance with an aspect of the disclosure, a method by base stationis provided. The method includes transmitting, to a terminal, firstinformation related to a length of a random access preamble and a firstsubcarrier spacing of a random access channel, transmitting, to theterminal, second information related to a second subcarrier spacing of aphysical uplink shared channel (PUSCH), and receiving the random accesspreamble based on an offset parameter which is identified based on thelength of the random access preamble, the first subcarrier spacing, andthe second subcarrier spacing, wherein the offset parameter is used toidentify a frequency resource of the random access channel.

In accordance with an aspect of the disclosure, a terminal is provided.The terminal includes a transceiver; and at least one processorconfigured to receive, from a base station, first information related toa length of a random access preamble and a first subcarrier spacing of arandom access channel, receive, from the base station, secondinformation related to a second subcarrier spacing of a physical uplinkshared channel (PUSCH), identify an offset parameter based on the lengthof the random access preamble, the first subcarrier spacing, and thesecond subcarrier spacing, the offset parameter being used to identify afrequency resource of the random access channel, and transmit the randomaccess preamble based on the offset parameter.

In accordance with an aspect of the disclosure, a base station isprovided. The base station includes a transceiver, and at least oneprocessor configured to determine a resource of a random access channel,transmit, to a terminal, first information related to a length of arandom access preamble and a first subcarrier spacing of a random accesschannel, transmit, to the terminal, second information related to asecond subcarrier spacing of a physical uplink shared channel (PUSCH),and receive the random access preamble based on an offset parameterwhich is identified based on the length of the random access preamble,the first subcarrier spacing, and the second subcarrier spacing, whereinthe offset parameter is used to identify a frequency resource of therandom access channel.

Meanwhile, in the drawings illustrating a method in embodiments, theorder of description does not necessarily correspond to the order ofexecution, and the order relationship may be changed or executed inparallel.

Alternatively, the drawings illustrating the method of the disclosuremay omit some of the elements and may include only some of the elementswithout impairing the essence of the disclosure.

Further, the method of the disclosure may be carried out in combinationwith some or all of the contents included in each embodiment withoutdeparting from the essence of the disclosure.

Computer-executable instructions or programs for implementing thefunctions of various embodiments of the disclosure may be recorded on acomputer-readable storage medium. Corresponding functions can berealized by having a computer system read programs recorded on therecording medium and execute these programs. The so-called “computersystem” herein may be a computer system embedded in the device, and mayinclude an operating system or hardware (such as a peripheral device).The “computer-readable storage medium” may be a semiconductor recordingmedium, an optical recording medium, a magnetic recording medium, ashort-time dynamic storage program recording medium, or any otherrecording media readable by a computer.

Various features or functional modules of the devices used in the aboveembodiments may be implemented or performed by circuitry (e.g., asingle-chip or multi-chip integrated circuit). Circuits designed toperform the functions described in the present specification may includegeneral purpose processors, digital signal processors (DSPs),application specific integrated circuits (ASICs), field programmablegate arrays (FPGAs), or other programmable logic devices, discrete Gateor transistor logic, discrete hardware components, or any combination ofthe above. A general-purpose processor may be a microprocessor or anyexisting processor, controller, microcontroller, or state machine. Theabove circuit may be a digital circuit or an analog circuit. In a caseof new integrated circuit technology that replaces existing integratedcircuits due to advances in semiconductor technology, one or moreembodiments of the disclosure may also be implemented using these newintegrated circuit technologies.

The skilled in the art will understand that the disclosure includesdevices that are involved in performing one or more of the operationsdescribed in the disclosure. These devices may be specially designed andmanufactured for the required purposes, or may also include knowndevices in general purpose computers. These devices have computerprograms stored thereon that are selectively activated or reconfigured.Such computer programs may be stored in a device (e.g., a computer)readable medium or in any type of medium suitable for storing electronicinstructions and coupled to a bus, including but not limited to anytypes of disks, including a floppy disk, a hard disk, an optical disk, aCD-ROM, and a magneto-optical disk, a ROM, a RAM, an erasableprogrammable read-only memory (EPROM), an electrically erasableprogrammable read-only memory (EEPROM), a flash memory, a magnetic card,or a light card. For example, a readable medium includes any medium thatstores or transmits information in a readable form by a device (e.g., acomputer).

The skilled in the art can understand that each block of thesestructural diagrams and/or block diagrams and/or flowcharts, andcombinations of blocks in these structural diagrams and/or blockdiagrams and/or flowcharts may be implemented by computer programinstructions. The skilled in the art can understand that these computerprogram instructions can be provided to a processor of a general-purposecomputer, a professional computer, or a processor for other programmabledata processing method, so that the schemes specified in one or moreblocks of the structural diagrams and/or block diagrams and/orflowcharts may be executed by the processor of the computer or thecomputer for other programmable data processing method.

The skilled in the art can understand that various operations, methods,measures, and schemes that have been discussed in the disclosure can bealternated, changed, combined, or deleted. Further, various operations,methods that have been discussed in the disclosure, and otheroperations, measures, and schemes in the process can also be alternated,changed, rearranged, decomposed, combined, or deleted. Further, variousoperations, methods, operations, measures, and schemes in the prior artand those disclosed in the disclosure may also be alternated, changed,rearranged, decomposed, combined, or deleted.

While the disclosure has been shown and described with reference tovarious embodiments thereof, it will be understood by those skilled inthe art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the disclosure as definedby the appended claims and their equivalents.

What is claimed is:
 1. A method performed by a terminal, the methodcomprising: receiving, from a base station, first information related toa length of a random access preamble and second information related to afirst subcarrier spacing of a random access channel; receiving, from thebase station, third information related to a second subcarrier spacingof a physical uplink shared channel (PUSCH); identifying an offsetparameter among a plurality of offset parameters, the offset parametercorresponding to the first information related to the length of therandom access preamble, the second information related to the firstsubcarrier spacing, and the third information related to the secondsubcarrier spacing; identifying a frequency resource of the randomaccess channel based on the offset parameter; and transmitting therandom access preamble based on the frequency resource.
 2. The method ofclaim 1, wherein the first information related to the length of therandom access preamble, the second information related to the firstsubcarrier spacing of the random access channel, and the thirdinformation related to the second subcarrier spacing of the PUSCH areused to identify a number of resource blocks of the random accesschannel.
 3. The method of claim 2, wherein the number of resource blocksis “6”, based on the length of the random access preamble being 839, thefirst subcarrier spacing being 1.25, and the second subcarrier spacingbeing 15, wherein the number of resource blocks is “3”, based on thelength of the random access preamble being 839, the first subcarrierspacing being 1.25, and the second subcarrier spacing being 30, whereinthe number of resource blocks is “2”, based on the length of the randomaccess preamble being 839, the first subcarrier spacing being 1.25, andthe second subcarrier spacing being 60, wherein the number of resourceblocks is “24”, based on the length of the random access preamble being839, the first subcarrier spacing being 5, and the second subcarrierspacing being 15, wherein the number of resource blocks is “12”, basedon the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 30,and wherein the number of resource blocks is “6”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being5, and the second subcarrier spacing being
 60. 4. The method of claim 1,wherein the offset parameter is “7”, based on the length of the randomaccess preamble being 839, the first subcarrier spacing being 1.25, andthe second subcarrier spacing being 15, wherein the offset parameter is“1”, based on the length of the random access preamble being 839, thefirst subcarrier spacing being 1.25, and the second subcarrier spacingbeing 30, wherein the offset parameter is “133”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being1.25, and the second subcarrier spacing being 60, wherein the offsetparameter is “12”, based on the length of the random access preamblebeing 839, the first subcarrier spacing being 5, and the secondsubcarrier spacing being 15, wherein the offset parameter is “10”, basedon the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 30,and wherein the offset parameter is “7”, based on the length of therandom access preamble being 839, the first subcarrier spacing being 5,and the second subcarrier spacing being
 60. 5. A method performed by abase station, the method comprising: transmitting, to a terminal, firstinformation related to a length of a random access preamble and secondinformation related to a first subcarrier spacing of a random accesschannel; transmitting, to the terminal, third information related to asecond subcarrier spacing of a physical uplink shared channel (PUSCH);and receiving the random access preamble based on a frequency resourceassociated with an offset parameter, the offset parameter correspondingto the first information related to the length of the random accesspreamble, the second information related to the first subcarrierspacing, and the third information related to the second subcarrierspacing among a plurality of offset parameters.
 6. The method of claim5, wherein the first information related to the length of the randomaccess preamble, the second information related to the first subcarrierspacing of the random access channel, and the third information relatedto the second subcarrier spacing of the PUSCH are used to identify anumber of resource blocks of the random access channel.
 7. The method ofclaim 6, wherein the number of resource blocks is “6”, based on thelength of the random access preamble being 839, the first subcarrierspacing being 1.25, and the second subcarrier spacing being 15, whereinthe number of resource blocks is “3”, based on the length of the randomaccess preamble being 839, the first subcarrier spacing being 1.25, andthe second subcarrier spacing being 30, wherein the number of resourceblocks is “2”, based on the length of the random access preamble being839, the first subcarrier spacing being 1.25, and the second subcarrierspacing being 60, wherein the number of resource blocks is “24”, basedon the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 15,wherein the number of resource blocks is “12”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being5, and the second subcarrier spacing being 30, and wherein the number ofresource blocks is “6”, based on the length of the random accesspreamble being 839, the first subcarrier spacing being 5, and the secondsubcarrier spacing being
 60. 8. The method of claim 5, wherein theoffset parameter is “7”, based on the length of the random accesspreamble being 839, the first subcarrier spacing being 1.25, and thesecond subcarrier spacing being 15, wherein the offset parameter is “1”,based on the length of the random access preamble being 839, the firstsubcarrier spacing being 1.25, and the second subcarrier spacing being30, wherein the offset parameter is “133”, based on the length of therandom access preamble being 839, the first subcarrier spacing being1.25, and the second subcarrier spacing being 60, wherein the offsetparameter is “12”, based on the length of the random access preamblebeing 839, the first subcarrier spacing being 5, and the secondsubcarrier spacing being 15, wherein the offset parameter is “10”, basedon the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 30,and wherein the offset parameter is “7”, based on the length of therandom access preamble being 839, the first subcarrier spacing being 5,and the second subcarrier spacing being
 60. 9. A terminal in a wirelesscommunication system, the terminal comprising: a transceiver; and atleast one processor coupled with the transceiver and configured to:receive, from a base station, first information related to a length of arandom access preamble and second information related to a firstsubcarrier spacing of a random access channel, receive, from the basestation, third information related to a second subcarrier spacing of aphysical uplink shared channel (PUSCH), identify an offset parameteramong a plurality of offset parameters, the offset parametercorresponding to the first information related to the length of therandom access preamble, the second information related to the firstsubcarrier spacing, and the third information related to the secondsubcarrier spacing, identify a frequency resource of the random accesschannel based on the offset parameter, and transmit the random accesspreamble based on the frequency resource.
 10. The terminal of claim 9,wherein the first information related to the length of the random accesspreamble, the second information related to the first subcarrier spacingof the random access channel, and the third information related to thesecond subcarrier spacing of the PUSCH are used to identify a number ofresource blocks of the random access channel.
 11. The terminal of claim10, wherein the number of resource blocks is “6”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being1.25, and the second subcarrier spacing being 15, wherein the number ofresource blocks is “3”, based on the length of the random accesspreamble being 839, the first subcarrier spacing being 1.25, and thesecond subcarrier spacing being 30, wherein the number of resourceblocks is “2”, based on the length of the random access preamble being839, the first subcarrier spacing being 1.25, and the second subcarrierspacing being 60, wherein the number of resource blocks is “24”, basedon the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 15,wherein the number of resource blocks is “12”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being5, and the second subcarrier spacing being 30, and wherein the number ofresource blocks is “6”, based on the length of the random accesspreamble being 839, the first subcarrier spacing being 5, and the secondsubcarrier spacing being
 60. 12. The terminal of claim 9, wherein theoffset parameter is “7”, based on the length of the random accesspreamble being 839, the first subcarrier spacing being 1.25, and thesecond subcarrier spacing being 15, wherein the offset parameter is “1”,based on the length of the random access preamble being 839, the firstsubcarrier spacing being 1.25, and the second subcarrier spacing being30, wherein the offset parameter is “133”, based on the length of therandom access preamble being 839, the first subcarrier spacing being1.25, and the second subcarrier spacing being 60, wherein the offsetparameter is “12”, based on the length of the random access preamblebeing 839, the first subcarrier spacing being 5, and the secondsubcarrier spacing being 15, wherein the offset parameter is “10”, basedon the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 30,and wherein the offset parameter is “7”, based on the length of therandom access preamble being 839, the first subcarrier spacing being 5,and the second subcarrier spacing being
 60. 13. A base station in awireless communication system, the base station comprising: atransceiver; and at least one processor coupled with the transceiver andconfigured to: determine a resource of a random access channel,transmit, to a terminal, first information related to a length of arandom access preamble and second information related to a firstsubcarrier spacing of the random access channel, transmit, to theterminal, third information related to a second subcarrier spacing of aphysical uplink shared channel (PUSCH), and receive the random accesspreamble based on a frequency resource associated with an offsetparameter, the offset parameter corresponding to the first informationrelated to the length of the random access preamble, the secondinformation related to the first subcarrier spacing, the thirdinformation related to the second subcarrier spacing among a pluralityof offset parameters.
 14. The base station of claim 13, wherein thefirst information related to the length of the random access preamble,the second information related to the first subcarrier spacing of therandom access channel, and the third information related to the secondsubcarrier spacing of the PUSCH are used to identify a number ofresource blocks of the random access channel.
 15. The base station ofclaim 14, wherein the offset parameter is “7”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being1.25, and the second subcarrier spacing being 15, wherein the offsetparameter is “1”, based on the length of the random access preamblebeing 839, the first subcarrier spacing being 1.25, and the secondsubcarrier spacing being 30, wherein the offset parameter is “133”,based on the length of the random access preamble being 839, the firstsubcarrier spacing being 1.25, and the second subcarrier spacing being60, wherein the offset parameter is “12”, based on the length of therandom access preamble being 839, the first subcarrier spacing being 5,and the second subcarrier spacing being 15, wherein the offset parameteris “10”, based on the length of the random access preamble being 839,the first subcarrier spacing being 5, and the second subcarrier spacingbeing 30, wherein the offset parameter is “7”, based on the length ofthe random access preamble being 839, the first subcarrier spacing being5, and the second subcarrier spacing being 60, wherein the number ofresource blocks is “6”, based on the length of the random accesspreamble being 839, the first subcarrier spacing being 1.25, and thesecond subcarrier spacing being 15, wherein the number of resourceblocks is “3”, based on the length of the random access preamble being839, the first subcarrier spacing being 1.25, and the second subcarrierspacing being 30, wherein the number of resource blocks is “2”, based onthe length of the random access preamble being 839, the first subcarrierspacing being 1.25, and the second subcarrier spacing being 60, whereinthe number of resource blocks is “24”, based on the length of the randomaccess preamble being 839, the first subcarrier spacing being 5, and thesecond subcarrier spacing being 15, wherein the number of resourceblocks is “12”, based on the length of the random access preamble being839, the first subcarrier spacing being 5, and the second subcarrierspacing being 30, and wherein the number of resource blocks is “6”,based on the length of the random access preamble being 839, the firstsubcarrier spacing being 5, and the second subcarrier spacing being 60.